vacuumlazy.c File Reference

#include "postgres.h"
#include <math.h>
#include "access/amapi.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/heapam_xlog.h"
#include "access/htup_details.h"
#include "access/multixact.h"
#include "access/transam.h"
#include "access/visibilitymap.h"
#include "access/xact.h"
#include "access/xlog.h"
#include "catalog/index.h"
#include "catalog/storage.h"
#include "commands/dbcommands.h"
#include "commands/progress.h"
#include "commands/vacuum.h"
#include "executor/instrument.h"
#include "miscadmin.h"
#include "optimizer/paths.h"
#include "pgstat.h"
#include "portability/instr_time.h"
#include "postmaster/autovacuum.h"
#include "storage/bufmgr.h"
#include "storage/freespace.h"
#include "storage/lmgr.h"
#include "tcop/tcopprot.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/pg_rusage.h"
#include "utils/timestamp.h"

Include dependency graph for vacuumlazy.c:

Go to the source code of this file.

Data Structures
struct	LVRelState
struct	LVPagePruneState
struct	LVSavedErrInfo

Macros
#define	REL_TRUNCATE_MINIMUM   1000
#define	REL_TRUNCATE_FRACTION   16
#define	VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL   20 /* ms */
#define	VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL   50 /* ms */
#define	VACUUM_TRUNCATE_LOCK_TIMEOUT   5000 /* ms */
#define	BYPASS_THRESHOLD_PAGES   0.02 /* i.e. 2% of rel_pages */
#define	FAILSAFE_EVERY_PAGES    ((BlockNumber) (((uint64) 4 * 1024 * 1024 * 1024) / BLCKSZ))
#define	VACUUM_FSM_EVERY_PAGES    ((BlockNumber) (((uint64) 8 * 1024 * 1024 * 1024) / BLCKSZ))
#define	SKIP_PAGES_THRESHOLD   ((BlockNumber) 32)
#define	PREFETCH_SIZE   ((BlockNumber) 32)
#define	ParallelVacuumIsActive(vacrel)   ((vacrel)->pvs != NULL)
#define	FORCE_CHECK_PAGE()    (blkno == nblocks - 1 && should_attempt_truncation(vacrel))

Typedefs
typedef struct LVRelState	LVRelState
typedef struct LVPagePruneState	LVPagePruneState
typedef struct LVSavedErrInfo	LVSavedErrInfo

Enumerations
enum	VacErrPhase {   VACUUM_ERRCB_PHASE_UNKNOWN , VACUUM_ERRCB_PHASE_SCAN_HEAP , VACUUM_ERRCB_PHASE_VACUUM_INDEX , VACUUM_ERRCB_PHASE_VACUUM_HEAP ,   VACUUM_ERRCB_PHASE_INDEX_CLEANUP , VACUUM_ERRCB_PHASE_TRUNCATE }

Functions
static void	lazy_scan_heap (LVRelState *vacrel, VacuumParams *params, bool aggressive)
static void	lazy_scan_prune (LVRelState *vacrel, Buffer buf, BlockNumber blkno, Page page, GlobalVisState *vistest, LVPagePruneState *prunestate)
static void	lazy_vacuum (LVRelState *vacrel)
static bool	lazy_vacuum_all_indexes (LVRelState *vacrel)
static void	lazy_vacuum_heap_rel (LVRelState *vacrel)
static int	lazy_vacuum_heap_page (LVRelState *vacrel, BlockNumber blkno, Buffer buffer, int index, Buffer *vmbuffer)
static bool	lazy_check_needs_freeze (Buffer buf, bool *hastup, LVRelState *vacrel)
static bool	lazy_check_wraparound_failsafe (LVRelState *vacrel)
static void	lazy_cleanup_all_indexes (LVRelState *vacrel)
static IndexBulkDeleteResult *	lazy_vacuum_one_index (Relation indrel, IndexBulkDeleteResult *istat, double reltuples, LVRelState *vacrel)
static IndexBulkDeleteResult *	lazy_cleanup_one_index (Relation indrel, IndexBulkDeleteResult *istat, double reltuples, bool estimated_count, LVRelState *vacrel)
static bool	should_attempt_truncation (LVRelState *vacrel)
static void	lazy_truncate_heap (LVRelState *vacrel)
static BlockNumber	count_nondeletable_pages (LVRelState *vacrel, bool *lock_waiter_detected)
static void	dead_items_alloc (LVRelState *vacrel, int nworkers)
static void	dead_items_cleanup (LVRelState *vacrel)
static bool	heap_page_is_all_visible (LVRelState *vacrel, Buffer buf, TransactionId *visibility_cutoff_xid, bool *all_frozen)
static void	update_index_statistics (LVRelState *vacrel)
static void	vacuum_error_callback (void *arg)
static void	update_vacuum_error_info (LVRelState *vacrel, LVSavedErrInfo *saved_vacrel, int phase, BlockNumber blkno, OffsetNumber offnum)
static void	restore_vacuum_error_info (LVRelState *vacrel, const LVSavedErrInfo *saved_vacrel)
void	heap_vacuum_rel (Relation rel, VacuumParams *params, BufferAccessStrategy bstrategy)
static int	dead_items_max_items (LVRelState *vacrel)

Macro Definition Documentation

BYPASS_THRESHOLD_PAGES

#define BYPASS_THRESHOLD_PAGES   0.02 /* i.e. 2% of rel_pages */

Definition at line 93 of file vacuumlazy.c.

FAILSAFE_EVERY_PAGES

#define FAILSAFE_EVERY_PAGES    ((BlockNumber) (((uint64) 4 * 1024 * 1024 * 1024) / BLCKSZ))

Definition at line 98 of file vacuumlazy.c.

FORCE_CHECK_PAGE

#define FORCE_CHECK_PAGE

(

)

(blkno == nblocks - 1 && should_attempt_truncation(vacrel))

ParallelVacuumIsActive

#define ParallelVacuumIsActive

(

vacrel

)

((vacrel)->pvs != NULL)

Definition at line 126 of file vacuumlazy.c.

PREFETCH_SIZE

#define PREFETCH_SIZE   ((BlockNumber) 32)

Definition at line 120 of file vacuumlazy.c.

REL_TRUNCATE_FRACTION

#define REL_TRUNCATE_FRACTION   16

Definition at line 76 of file vacuumlazy.c.

REL_TRUNCATE_MINIMUM

#define REL_TRUNCATE_MINIMUM   1000

Definition at line 75 of file vacuumlazy.c.

SKIP_PAGES_THRESHOLD

#define SKIP_PAGES_THRESHOLD   ((BlockNumber) 32)

Definition at line 114 of file vacuumlazy.c.

VACUUM_FSM_EVERY_PAGES

#define VACUUM_FSM_EVERY_PAGES    ((BlockNumber) (((uint64) 8 * 1024 * 1024 * 1024) / BLCKSZ))

Definition at line 107 of file vacuumlazy.c.

VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL

#define VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL   20 /* ms */

Definition at line 85 of file vacuumlazy.c.

VACUUM_TRUNCATE_LOCK_TIMEOUT

#define VACUUM_TRUNCATE_LOCK_TIMEOUT   5000 /* ms */

Definition at line 87 of file vacuumlazy.c.

VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL

#define VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL   50 /* ms */

Definition at line 86 of file vacuumlazy.c.

Typedef Documentation

LVPagePruneState

typedef struct LVPagePruneState LVPagePruneState

LVRelState

typedef struct LVRelState LVRelState

LVSavedErrInfo

typedef struct LVSavedErrInfo LVSavedErrInfo

Enumeration Type Documentation

VacErrPhase

enum VacErrPhase

Enumerator
VACUUM_ERRCB_PHASE_UNKNOWN
VACUUM_ERRCB_PHASE_SCAN_HEAP
VACUUM_ERRCB_PHASE_VACUUM_INDEX
VACUUM_ERRCB_PHASE_VACUUM_HEAP
VACUUM_ERRCB_PHASE_INDEX_CLEANUP
VACUUM_ERRCB_PHASE_TRUNCATE

Definition at line 129 of file vacuumlazy.c.

{
    VACUUM_ERRCB_PHASE_UNKNOWN,
    VACUUM_ERRCB_PHASE_SCAN_HEAP,
    VACUUM_ERRCB_PHASE_VACUUM_INDEX,
    VACUUM_ERRCB_PHASE_VACUUM_HEAP,
    VACUUM_ERRCB_PHASE_INDEX_CLEANUP,
    VACUUM_ERRCB_PHASE_TRUNCATE
} VacErrPhase;

Function Documentation

count_nondeletable_pages()

static BlockNumber count_nondeletable_pages ( LVRelState *  vacrel, bool *  lock_waiter_detected  )

static

Definition at line 2705 of file vacuumlazy.c.

{
    BlockNumber blkno;
    BlockNumber prefetchedUntil;
    instr_time  starttime;
 
    /* Initialize the starttime if we check for conflicting lock requests */
    INSTR_TIME_SET_CURRENT(starttime);
 
    /*
     * Start checking blocks at what we believe relation end to be and move
     * backwards.  (Strange coding of loop control is needed because blkno is
     * unsigned.)  To make the scan faster, we prefetch a few blocks at a time
     * in forward direction, so that OS-level readahead can kick in.
     */
    blkno = vacrel->rel_pages;
    StaticAssertStmt((PREFETCH_SIZE & (PREFETCH_SIZE - 1)) == 0,
                     "prefetch size must be power of 2");
    prefetchedUntil = InvalidBlockNumber;
    while (blkno > vacrel->nonempty_pages)
    {
        Buffer      buf;
        Page        page;
        OffsetNumber offnum,
                    maxoff;
        bool        hastup;
 
        /*
         * Check if another process requests a lock on our relation. We are
         * holding an AccessExclusiveLock here, so they will be waiting. We
         * only do this once per VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL, and we
         * only check if that interval has elapsed once every 32 blocks to
         * keep the number of system calls and actual shared lock table
         * lookups to a minimum.
         */
        if ((blkno % 32) == 0)
        {
            instr_time  currenttime;
            instr_time  elapsed;
 
            INSTR_TIME_SET_CURRENT(currenttime);
            elapsed = currenttime;
            INSTR_TIME_SUBTRACT(elapsed, starttime);
            if ((INSTR_TIME_GET_MICROSEC(elapsed) / 1000)
                >= VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL)
            {
                if (LockHasWaitersRelation(vacrel->rel, AccessExclusiveLock))
                {
                    ereport(vacrel->verbose ? INFO : DEBUG2,
                            (errmsg("table \"%s\": suspending truncate due to conflicting lock request",
                                    vacrel->relname)));
 
                    *lock_waiter_detected = true;
                    return blkno;
                }
                starttime = currenttime;
            }
        }
 
        /*
         * We don't insert a vacuum delay point here, because we have an
         * exclusive lock on the table which we want to hold for as short a
         * time as possible.  We still need to check for interrupts however.
         */
        CHECK_FOR_INTERRUPTS();
 
        blkno--;
 
        /* If we haven't prefetched this lot yet, do so now. */
        if (prefetchedUntil > blkno)
        {
            BlockNumber prefetchStart;
            BlockNumber pblkno;
 
            prefetchStart = blkno & ~(PREFETCH_SIZE - 1);
            for (pblkno = prefetchStart; pblkno <= blkno; pblkno++)
            {
                PrefetchBuffer(vacrel->rel, MAIN_FORKNUM, pblkno);
                CHECK_FOR_INTERRUPTS();
            }
            prefetchedUntil = prefetchStart;
        }
 
        buf = ReadBufferExtended(vacrel->rel, MAIN_FORKNUM, blkno, RBM_NORMAL,
                                 vacrel->bstrategy);
 
        /* In this phase we only need shared access to the buffer */
        LockBuffer(buf, BUFFER_LOCK_SHARE);
 
        page = BufferGetPage(buf);
 
        if (PageIsNew(page) || PageIsEmpty(page))
        {
            UnlockReleaseBuffer(buf);
            continue;
        }
 
        hastup = false;
        maxoff = PageGetMaxOffsetNumber(page);
        for (offnum = FirstOffsetNumber;
             offnum <= maxoff;
             offnum = OffsetNumberNext(offnum))
        {
            ItemId      itemid;
 
            itemid = PageGetItemId(page, offnum);
 
            /*
             * Note: any non-unused item should be taken as a reason to keep
             * this page.  Even an LP_DEAD item makes truncation unsafe, since
             * we must not have cleaned out its index entries.
             */
            if (ItemIdIsUsed(itemid))
            {
                hastup = true;
                break;          /* can stop scanning */
            }
        }                       /* scan along page */
 
        UnlockReleaseBuffer(buf);
 
        /* Done scanning if we found a tuple here */
        if (hastup)
            return blkno + 1;
    }
 
    /*
     * If we fall out of the loop, all the previously-thought-to-be-empty
     * pages still are; we need not bother to look at the last known-nonempty
     * page.
     */
    return vacrel->nonempty_pages;
}

References AccessExclusiveLock, LVRelState::bstrategy, buf, BUFFER_LOCK_SHARE, BufferGetPage, CHECK_FOR_INTERRUPTS, DEBUG2, ereport, errmsg(), FirstOffsetNumber, INFO, INSTR_TIME_GET_MICROSEC, INSTR_TIME_SET_CURRENT, INSTR_TIME_SUBTRACT, InvalidBlockNumber, ItemIdIsUsed, LockBuffer(), LockHasWaitersRelation(), MAIN_FORKNUM, LVRelState::nonempty_pages, OffsetNumberNext, PageGetItemId, PageGetMaxOffsetNumber, PageIsEmpty, PageIsNew, PREFETCH_SIZE, PrefetchBuffer(), RBM_NORMAL, ReadBufferExtended(), LVRelState::rel, LVRelState::rel_pages, LVRelState::relname, StaticAssertStmt, UnlockReleaseBuffer(), VACUUM_TRUNCATE_LOCK_CHECK_INTERVAL, and LVRelState::verbose.

Referenced by lazy_truncate_heap().

dead_items_alloc()

static void dead_items_alloc ( LVRelState *  vacrel, int  nworkers  )

static

Definition at line 2887 of file vacuumlazy.c.

{
    VacDeadItems *dead_items;
    int         max_items;
 
    max_items = dead_items_max_items(vacrel);
    Assert(max_items >= MaxHeapTuplesPerPage);
 
    /*
     * Initialize state for a parallel vacuum.  As of now, only one worker can
     * be used for an index, so we invoke parallelism only if there are at
     * least two indexes on a table.
     */
    if (nworkers >= 0 && vacrel->nindexes > 1 && vacrel->do_index_vacuuming)
    {
        /*
         * Since parallel workers cannot access data in temporary tables, we
         * can't perform parallel vacuum on them.
         */
        if (RelationUsesLocalBuffers(vacrel->rel))
        {
            /*
             * Give warning only if the user explicitly tries to perform a
             * parallel vacuum on the temporary table.
             */
            if (nworkers > 0)
                ereport(WARNING,
                        (errmsg("disabling parallel option of vacuum on \"%s\" --- cannot vacuum temporary tables in parallel",
                                vacrel->relname)));
        }
        else
            vacrel->pvs = parallel_vacuum_init(vacrel->rel, vacrel->indrels,
                                               vacrel->nindexes, nworkers,
                                               max_items,
                                               vacrel->verbose ? INFO : DEBUG2,
                                               vacrel->bstrategy);
 
        /* If parallel mode started, dead_items space is allocated in DSM */
        if (ParallelVacuumIsActive(vacrel))
        {
            vacrel->dead_items = parallel_vacuum_get_dead_items(vacrel->pvs);
            return;
        }
    }
 
    /* Serial VACUUM case */
    dead_items = (VacDeadItems *) palloc(vac_max_items_to_alloc_size(max_items));
    dead_items->max_items = max_items;
    dead_items->num_items = 0;
 
    vacrel->dead_items = dead_items;
}

References Assert(), LVRelState::bstrategy, LVRelState::dead_items, dead_items_max_items(), DEBUG2, LVRelState::do_index_vacuuming, ereport, errmsg(), LVRelState::indrels, INFO, VacDeadItems::max_items, MaxHeapTuplesPerPage, LVRelState::nindexes, VacDeadItems::num_items, palloc(), parallel_vacuum_get_dead_items(), parallel_vacuum_init(), ParallelVacuumIsActive, LVRelState::pvs, LVRelState::rel, RelationUsesLocalBuffers, LVRelState::relname, vac_max_items_to_alloc_size(), LVRelState::verbose, and WARNING.

Referenced by lazy_scan_heap().

dead_items_cleanup()

static void dead_items_cleanup ( LVRelState *  vacrel )

static

Definition at line 2944 of file vacuumlazy.c.

{
    if (!ParallelVacuumIsActive(vacrel))
    {
        /* Don't bother with pfree here */
        return;
    }
 
    /* End parallel mode */
    parallel_vacuum_end(vacrel->pvs, vacrel->indstats);
    vacrel->pvs = NULL;
}

References LVRelState::indstats, parallel_vacuum_end(), ParallelVacuumIsActive, and LVRelState::pvs.

Referenced by lazy_scan_heap().

dead_items_max_items()

static int dead_items_max_items ( LVRelState *  vacrel )

static

Definition at line 2848 of file vacuumlazy.c.

{
    int64       max_items;
    int         vac_work_mem = IsAutoVacuumWorkerProcess() &&
    autovacuum_work_mem != -1 ?
    autovacuum_work_mem : maintenance_work_mem;
 
    if (vacrel->nindexes > 0)
    {
        BlockNumber rel_pages = vacrel->rel_pages;
 
        max_items = MAXDEADITEMS(vac_work_mem * 1024L);
        max_items = Min(max_items, INT_MAX);
        max_items = Min(max_items, MAXDEADITEMS(MaxAllocSize));
 
        /* curious coding here to ensure the multiplication can't overflow */
        if ((BlockNumber) (max_items / MaxHeapTuplesPerPage) > rel_pages)
            max_items = rel_pages * MaxHeapTuplesPerPage;
 
        /* stay sane if small maintenance_work_mem */
        max_items = Max(max_items, MaxHeapTuplesPerPage);
    }
    else
    {
        /* One-pass case only stores a single heap page's TIDs at a time */
        max_items = MaxHeapTuplesPerPage;
    }
 
    return (int) max_items;
}

References autovacuum_work_mem, IsAutoVacuumWorkerProcess(), maintenance_work_mem, Max, MaxAllocSize, MAXDEADITEMS, MaxHeapTuplesPerPage, Min, LVRelState::nindexes, and LVRelState::rel_pages.

Referenced by dead_items_alloc().

heap_page_is_all_visible()

static bool heap_page_is_all_visible ( LVRelState *  vacrel, Buffer  buf, TransactionId *  visibility_cutoff_xid, bool *  all_frozen  )

static

Definition at line 2969 of file vacuumlazy.c.

{
    Page        page = BufferGetPage(buf);
    BlockNumber blockno = BufferGetBlockNumber(buf);
    OffsetNumber offnum,
                maxoff;
    bool        all_visible = true;
 
    *visibility_cutoff_xid = InvalidTransactionId;
    *all_frozen = true;
 
    maxoff = PageGetMaxOffsetNumber(page);
    for (offnum = FirstOffsetNumber;
         offnum <= maxoff && all_visible;
         offnum = OffsetNumberNext(offnum))
    {
        ItemId      itemid;
        HeapTupleData tuple;
 
        /*
         * Set the offset number so that we can display it along with any
         * error that occurred while processing this tuple.
         */
        vacrel->offnum = offnum;
        itemid = PageGetItemId(page, offnum);
 
        /* Unused or redirect line pointers are of no interest */
        if (!ItemIdIsUsed(itemid) || ItemIdIsRedirected(itemid))
            continue;
 
        ItemPointerSet(&(tuple.t_self), blockno, offnum);
 
        /*
         * Dead line pointers can have index pointers pointing to them. So
         * they can't be treated as visible
         */
        if (ItemIdIsDead(itemid))
        {
            all_visible = false;
            *all_frozen = false;
            break;
        }
 
        Assert(ItemIdIsNormal(itemid));
 
        tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
        tuple.t_len = ItemIdGetLength(itemid);
        tuple.t_tableOid = RelationGetRelid(vacrel->rel);
 
        switch (HeapTupleSatisfiesVacuum(&tuple, vacrel->OldestXmin, buf))
        {
            case HEAPTUPLE_LIVE:
                {
                    TransactionId xmin;
 
                    /* Check comments in lazy_scan_prune. */
                    if (!HeapTupleHeaderXminCommitted(tuple.t_data))
                    {
                        all_visible = false;
                        *all_frozen = false;
                        break;
                    }
 
                    /*
                     * The inserter definitely committed. But is it old enough
                     * that everyone sees it as committed?
                     */
                    xmin = HeapTupleHeaderGetXmin(tuple.t_data);
                    if (!TransactionIdPrecedes(xmin, vacrel->OldestXmin))
                    {
                        all_visible = false;
                        *all_frozen = false;
                        break;
                    }
 
                    /* Track newest xmin on page. */
                    if (TransactionIdFollows(xmin, *visibility_cutoff_xid))
                        *visibility_cutoff_xid = xmin;
 
                    /* Check whether this tuple is already frozen or not */
                    if (all_visible && *all_frozen &&
                        heap_tuple_needs_eventual_freeze(tuple.t_data))
                        *all_frozen = false;
                }
                break;
 
            case HEAPTUPLE_DEAD:
            case HEAPTUPLE_RECENTLY_DEAD:
            case HEAPTUPLE_INSERT_IN_PROGRESS:
            case HEAPTUPLE_DELETE_IN_PROGRESS:
                {
                    all_visible = false;
                    *all_frozen = false;
                    break;
                }
            default:
                elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
                break;
        }
    }                           /* scan along page */
 
    /* Clear the offset information once we have processed the given page. */
    vacrel->offnum = InvalidOffsetNumber;
 
    return all_visible;
}

References Assert(), buf, BufferGetBlockNumber(), BufferGetPage, elog, ERROR, FirstOffsetNumber, heap_tuple_needs_eventual_freeze(), HEAPTUPLE_DEAD, HEAPTUPLE_DELETE_IN_PROGRESS, HEAPTUPLE_INSERT_IN_PROGRESS, HEAPTUPLE_LIVE, HEAPTUPLE_RECENTLY_DEAD, HeapTupleHeaderGetXmin, HeapTupleHeaderXminCommitted, HeapTupleSatisfiesVacuum(), InvalidOffsetNumber, InvalidTransactionId, ItemIdGetLength, ItemIdIsDead, ItemIdIsNormal, ItemIdIsRedirected, ItemIdIsUsed, ItemPointerSet, LVRelState::offnum, OffsetNumberNext, LVRelState::OldestXmin, PageGetItem, PageGetItemId, PageGetMaxOffsetNumber, LVRelState::rel, RelationGetRelid, HeapTupleData::t_data, HeapTupleData::t_len, HeapTupleData::t_self, HeapTupleData::t_tableOid, TransactionIdFollows(), and TransactionIdPrecedes().

Referenced by lazy_scan_prune(), and lazy_vacuum_heap_page().

heap_vacuum_rel()

void heap_vacuum_rel	(	Relation	rel,
		VacuumParams *	params,
		BufferAccessStrategy	bstrategy
	)

Definition at line 296 of file vacuumlazy.c.

{
    LVRelState *vacrel;
    bool        verbose,
                instrument;
    PGRUsage    ru0;
    TimestampTz starttime = 0;
    WalUsage    walusage_start = pgWalUsage;
    WalUsage    walusage = {0, 0, 0};
    long        secs;
    int         usecs;
    double      read_rate,
                write_rate;
    bool        aggressive;     /* should we scan all unfrozen pages? */
    bool        scanned_all_unfrozen;   /* actually scanned all such pages? */
    char      **indnames = NULL;
    TransactionId xidFullScanLimit;
    MultiXactId mxactFullScanLimit;
    BlockNumber new_rel_pages;
    BlockNumber new_rel_allvisible;
    double      new_live_tuples;
    TransactionId new_frozen_xid;
    MultiXactId new_min_multi;
    ErrorContextCallback errcallback;
    PgStat_Counter startreadtime = 0;
    PgStat_Counter startwritetime = 0;
    TransactionId OldestXmin;
    TransactionId FreezeLimit;
    MultiXactId MultiXactCutoff;
 
    verbose = (params->options & VACOPT_VERBOSE) != 0;
    instrument = (verbose || (IsAutoVacuumWorkerProcess() &&
                              params->log_min_duration >= 0));
    if (instrument)
    {
        pg_rusage_init(&ru0);
        starttime = GetCurrentTimestamp();
        if (track_io_timing)
        {
            startreadtime = pgStatBlockReadTime;
            startwritetime = pgStatBlockWriteTime;
        }
    }
 
    pgstat_progress_start_command(PROGRESS_COMMAND_VACUUM,
                                  RelationGetRelid(rel));
 
    vacuum_set_xid_limits(rel,
                          params->freeze_min_age,
                          params->freeze_table_age,
                          params->multixact_freeze_min_age,
                          params->multixact_freeze_table_age,
                          &OldestXmin, &FreezeLimit, &xidFullScanLimit,
                          &MultiXactCutoff, &mxactFullScanLimit);
 
    /*
     * We request an aggressive scan if the table's frozen Xid is now older
     * than or equal to the requested Xid full-table scan limit; or if the
     * table's minimum MultiXactId is older than or equal to the requested
     * mxid full-table scan limit; or if DISABLE_PAGE_SKIPPING was specified.
     */
    aggressive = TransactionIdPrecedesOrEquals(rel->rd_rel->relfrozenxid,
                                               xidFullScanLimit);
    aggressive |= MultiXactIdPrecedesOrEquals(rel->rd_rel->relminmxid,
                                              mxactFullScanLimit);
    if (params->options & VACOPT_DISABLE_PAGE_SKIPPING)
        aggressive = true;
 
    /*
     * Setup error traceback support for ereport() first.  The idea is to set
     * up an error context callback to display additional information on any
     * error during a vacuum.  During different phases of vacuum, we update
     * the state so that the error context callback always display current
     * information.
     *
     * Copy the names of heap rel into local memory for error reporting
     * purposes, too.  It isn't always safe to assume that we can get the name
     * of each rel.  It's convenient for code in lazy_scan_heap to always use
     * these temp copies.
     */
    vacrel = (LVRelState *) palloc0(sizeof(LVRelState));
    vacrel->relnamespace = get_namespace_name(RelationGetNamespace(rel));
    vacrel->relname = pstrdup(RelationGetRelationName(rel));
    vacrel->indname = NULL;
    vacrel->phase = VACUUM_ERRCB_PHASE_UNKNOWN;
    vacrel->verbose = verbose;
    errcallback.callback = vacuum_error_callback;
    errcallback.arg = vacrel;
    errcallback.previous = error_context_stack;
    error_context_stack = &errcallback;
    if (verbose)
    {
        Assert(!IsAutoVacuumWorkerProcess());
        if (aggressive)
            ereport(INFO,
                    (errmsg("aggressively vacuuming \"%s.%s.%s\"",
                            get_database_name(MyDatabaseId),
                            vacrel->relnamespace, vacrel->relname)));
        else
            ereport(INFO,
                    (errmsg("vacuuming \"%s.%s.%s\"",
                            get_database_name(MyDatabaseId),
                            vacrel->relnamespace, vacrel->relname)));
    }
 
    /* Set up high level stuff about rel and its indexes */
    vacrel->rel = rel;
    vac_open_indexes(vacrel->rel, RowExclusiveLock, &vacrel->nindexes,
                     &vacrel->indrels);
    if (instrument && vacrel->nindexes > 0)
    {
        /* Copy index names used by instrumentation (not error reporting) */
        indnames = palloc(sizeof(char *) * vacrel->nindexes);
        for (int i = 0; i < vacrel->nindexes; i++)
            indnames[i] = pstrdup(RelationGetRelationName(vacrel->indrels[i]));
    }
 
    /*
     * The index_cleanup param either disables index vacuuming and cleanup or
     * forces it to go ahead when we would otherwise apply the index bypass
     * optimization.  The default is 'auto', which leaves the final decision
     * up to lazy_vacuum().
     *
     * The truncate param allows user to avoid attempting relation truncation,
     * though it can't force truncation to happen.
     */
    Assert(params->index_cleanup != VACOPTVALUE_UNSPECIFIED);
    Assert(params->truncate != VACOPTVALUE_UNSPECIFIED &&
           params->truncate != VACOPTVALUE_AUTO);
    vacrel->failsafe_active = false;
    vacrel->consider_bypass_optimization = true;
    vacrel->do_index_vacuuming = true;
    vacrel->do_index_cleanup = true;
    vacrel->do_rel_truncate = (params->truncate != VACOPTVALUE_DISABLED);
    if (params->index_cleanup == VACOPTVALUE_DISABLED)
    {
        /* Force disable index vacuuming up-front */
        vacrel->do_index_vacuuming = false;
        vacrel->do_index_cleanup = false;
    }
    else if (params->index_cleanup == VACOPTVALUE_ENABLED)
    {
        /* Force index vacuuming.  Note that failsafe can still bypass. */
        vacrel->consider_bypass_optimization = false;
    }
    else
    {
        /* Default/auto, make all decisions dynamically */
        Assert(params->index_cleanup == VACOPTVALUE_AUTO);
    }
 
    vacrel->bstrategy = bstrategy;
    vacrel->relfrozenxid = rel->rd_rel->relfrozenxid;
    vacrel->relminmxid = rel->rd_rel->relminmxid;
    vacrel->old_live_tuples = rel->rd_rel->reltuples;
 
    /* Set cutoffs for entire VACUUM */
    vacrel->OldestXmin = OldestXmin;
    vacrel->FreezeLimit = FreezeLimit;
    vacrel->MultiXactCutoff = MultiXactCutoff;
 
    /*
     * Call lazy_scan_heap to perform all required heap pruning, index
     * vacuuming, and heap vacuuming (plus related processing)
     */
    lazy_scan_heap(vacrel, params, aggressive);
 
    /* Done with indexes */
    vac_close_indexes(vacrel->nindexes, vacrel->indrels, NoLock);
 
    /*
     * Compute whether we actually scanned the all unfrozen pages. If we did,
     * we can adjust relfrozenxid and relminmxid.
     *
     * NB: We need to check this before truncating the relation, because that
     * will change ->rel_pages.
     */
    if ((vacrel->scanned_pages + vacrel->frozenskipped_pages)
        < vacrel->rel_pages)
    {
        Assert(!aggressive);
        scanned_all_unfrozen = false;
    }
    else
        scanned_all_unfrozen = true;
 
    /*
     * Optionally truncate the relation.
     */
    if (should_attempt_truncation(vacrel))
    {
        update_vacuum_error_info(vacrel, NULL, VACUUM_ERRCB_PHASE_TRUNCATE,
                                 vacrel->nonempty_pages,
                                 InvalidOffsetNumber);
        lazy_truncate_heap(vacrel);
    }
 
    /* Pop the error context stack */
    error_context_stack = errcallback.previous;
 
    /* Report that we are now doing final cleanup */
    pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                 PROGRESS_VACUUM_PHASE_FINAL_CLEANUP);
 
    /*
     * Update statistics in pg_class.
     *
     * In principle new_live_tuples could be -1 indicating that we (still)
     * don't know the tuple count.  In practice that probably can't happen,
     * since we'd surely have scanned some pages if the table is new and
     * nonempty.
     *
     * For safety, clamp relallvisible to be not more than what we're setting
     * relpages to.
     *
     * Also, don't change relfrozenxid/relminmxid if we skipped any pages,
     * since then we don't know for certain that all tuples have a newer xmin.
     */
    new_rel_pages = vacrel->rel_pages;
    new_live_tuples = vacrel->new_live_tuples;
 
    visibilitymap_count(rel, &new_rel_allvisible, NULL);
    if (new_rel_allvisible > new_rel_pages)
        new_rel_allvisible = new_rel_pages;
 
    new_frozen_xid = scanned_all_unfrozen ? FreezeLimit : InvalidTransactionId;
    new_min_multi = scanned_all_unfrozen ? MultiXactCutoff : InvalidMultiXactId;
 
    vac_update_relstats(rel,
                        new_rel_pages,
                        new_live_tuples,
                        new_rel_allvisible,
                        vacrel->nindexes > 0,
                        new_frozen_xid,
                        new_min_multi,
                        false);
 
    /*
     * Report results to the stats collector, too.
     *
     * Deliberately avoid telling the stats collector about LP_DEAD items that
     * remain in the table due to VACUUM bypassing index and heap vacuuming.
     * ANALYZE will consider the remaining LP_DEAD items to be dead "tuples".
     * It seems like a good idea to err on the side of not vacuuming again too
     * soon in cases where the failsafe prevented significant amounts of heap
     * vacuuming.
     */
    pgstat_report_vacuum(RelationGetRelid(rel),
                         rel->rd_rel->relisshared,
                         Max(new_live_tuples, 0),
                         vacrel->new_dead_tuples);
    pgstat_progress_end_command();
 
    if (instrument)
    {
        TimestampTz endtime = GetCurrentTimestamp();
 
        if (verbose || params->log_min_duration == 0 ||
            TimestampDifferenceExceeds(starttime, endtime,
                                       params->log_min_duration))
        {
            StringInfoData buf;
            char       *msgfmt;
            BlockNumber orig_rel_pages;
 
            TimestampDifference(starttime, endtime, &secs, &usecs);
 
            memset(&walusage, 0, sizeof(WalUsage));
            WalUsageAccumDiff(&walusage, &pgWalUsage, &walusage_start);
 
            read_rate = 0;
            write_rate = 0;
            if ((secs > 0) || (usecs > 0))
            {
                read_rate = (double) BLCKSZ * VacuumPageMiss / (1024 * 1024) /
                    (secs + usecs / 1000000.0);
                write_rate = (double) BLCKSZ * VacuumPageDirty / (1024 * 1024) /
                    (secs + usecs / 1000000.0);
            }
 
            initStringInfo(&buf);
            if (verbose)
            {
                /*
                 * Aggressiveness already reported earlier, in dedicated
                 * VACUUM VERBOSE ereport
                 */
                Assert(!params->is_wraparound);
                msgfmt = _("finished vacuuming \"%s.%s.%s\": index scans: %d\n");
            }
            else if (params->is_wraparound)
            {
                /*
                 * While it's possible for a VACUUM to be both is_wraparound
                 * and !aggressive, that's just a corner-case -- is_wraparound
                 * implies aggressive.  Produce distinct output for the corner
                 * case all the same, just in case.
                 */
                if (aggressive)
                    msgfmt = _("automatic aggressive vacuum to prevent wraparound of table \"%s.%s.%s\": index scans: %d\n");
                else
                    msgfmt = _("automatic vacuum to prevent wraparound of table \"%s.%s.%s\": index scans: %d\n");
            }
            else
            {
                if (aggressive)
                    msgfmt = _("automatic aggressive vacuum of table \"%s.%s.%s\": index scans: %d\n");
                else
                    msgfmt = _("automatic vacuum of table \"%s.%s.%s\": index scans: %d\n");
            }
            appendStringInfo(&buf, msgfmt,
                             get_database_name(MyDatabaseId),
                             vacrel->relnamespace,
                             vacrel->relname,
                             vacrel->num_index_scans);
            appendStringInfo(&buf, _("pages: %u removed, %u remain, %u skipped due to pins, %u skipped frozen\n"),
                             vacrel->pages_removed,
                             vacrel->rel_pages,
                             vacrel->pinskipped_pages,
                             vacrel->frozenskipped_pages);
            appendStringInfo(&buf,
                             _("tuples: %lld removed, %lld remain, %lld are dead but not yet removable, oldest xmin: %u\n"),
                             (long long) vacrel->tuples_deleted,
                             (long long) vacrel->new_rel_tuples,
                             (long long) vacrel->new_dead_tuples,
                             OldestXmin);
            orig_rel_pages = vacrel->rel_pages + vacrel->pages_removed;
            if (orig_rel_pages > 0)
            {
                if (vacrel->do_index_vacuuming)
                {
                    if (vacrel->nindexes == 0 || vacrel->num_index_scans == 0)
                        appendStringInfoString(&buf, _("index scan not needed: "));
                    else
                        appendStringInfoString(&buf, _("index scan needed: "));
 
                    msgfmt = _("%u pages from table (%.2f%% of total) had %lld dead item identifiers removed\n");
                }
                else
                {
                    if (!vacrel->failsafe_active)
                        appendStringInfoString(&buf, _("index scan bypassed: "));
                    else
                        appendStringInfoString(&buf, _("index scan bypassed by failsafe: "));
 
                    msgfmt = _("%u pages from table (%.2f%% of total) have %lld dead item identifiers\n");
                }
                appendStringInfo(&buf, msgfmt,
                                 vacrel->lpdead_item_pages,
                                 100.0 * vacrel->lpdead_item_pages / orig_rel_pages,
                                 (long long) vacrel->lpdead_items);
            }
            for (int i = 0; i < vacrel->nindexes; i++)
            {
                IndexBulkDeleteResult *istat = vacrel->indstats[i];
 
                if (!istat)
                    continue;
 
                appendStringInfo(&buf,
                                 _("index \"%s\": pages: %u in total, %u newly deleted, %u currently deleted, %u reusable\n"),
                                 indnames[i],
                                 istat->num_pages,
                                 istat->pages_newly_deleted,
                                 istat->pages_deleted,
                                 istat->pages_free);
            }
            if (track_io_timing)
            {
                double      read_ms = (double) (pgStatBlockReadTime - startreadtime) / 1000;
                double      write_ms = (double) (pgStatBlockWriteTime - startwritetime) / 1000;
 
                appendStringInfo(&buf, _("I/O timings: read: %.3f ms, write: %.3f ms\n"),
                                 read_ms, write_ms);
            }
            appendStringInfo(&buf, _("avg read rate: %.3f MB/s, avg write rate: %.3f MB/s\n"),
                             read_rate, write_rate);
            appendStringInfo(&buf,
                             _("buffer usage: %lld hits, %lld misses, %lld dirtied\n"),
                             (long long) VacuumPageHit,
                             (long long) VacuumPageMiss,
                             (long long) VacuumPageDirty);
            appendStringInfo(&buf,
                             _("WAL usage: %lld records, %lld full page images, %llu bytes\n"),
                             (long long) walusage.wal_records,
                             (long long) walusage.wal_fpi,
                             (unsigned long long) walusage.wal_bytes);
            appendStringInfo(&buf, _("system usage: %s"), pg_rusage_show(&ru0));
 
            ereport(verbose ? INFO : LOG,
                    (errmsg_internal("%s", buf.data)));
            pfree(buf.data);
        }
    }
 
    /* Cleanup index statistics and index names */
    for (int i = 0; i < vacrel->nindexes; i++)
    {
        if (vacrel->indstats[i])
            pfree(vacrel->indstats[i]);
 
        if (instrument)
            pfree(indnames[i]);
    }
}

References _, appendStringInfo(), appendStringInfoString(), ErrorContextCallback::arg, Assert(), LVRelState::bstrategy, buf, ErrorContextCallback::callback, LVRelState::consider_bypass_optimization, LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, LVRelState::do_rel_truncate, ereport, errmsg(), errmsg_internal(), error_context_stack, LVRelState::failsafe_active, VacuumParams::freeze_min_age, VacuumParams::freeze_table_age, LVRelState::FreezeLimit, LVRelState::frozenskipped_pages, get_database_name(), get_namespace_name(), GetCurrentTimestamp(), i, VacuumParams::index_cleanup, LVRelState::indname, LVRelState::indrels, LVRelState::indstats, INFO, initStringInfo(), InvalidMultiXactId, InvalidOffsetNumber, InvalidTransactionId, VacuumParams::is_wraparound, IsAutoVacuumWorkerProcess(), lazy_scan_heap(), lazy_truncate_heap(), LOG, VacuumParams::log_min_duration, LVRelState::lpdead_item_pages, LVRelState::lpdead_items, Max, VacuumParams::multixact_freeze_min_age, VacuumParams::multixact_freeze_table_age, LVRelState::MultiXactCutoff, MultiXactIdPrecedesOrEquals(), MyDatabaseId, LVRelState::new_dead_tuples, LVRelState::new_live_tuples, LVRelState::new_rel_tuples, LVRelState::nindexes, NoLock, LVRelState::nonempty_pages, LVRelState::num_index_scans, IndexBulkDeleteResult::num_pages, LVRelState::old_live_tuples, LVRelState::OldestXmin, VacuumParams::options, IndexBulkDeleteResult::pages_deleted, IndexBulkDeleteResult::pages_free, IndexBulkDeleteResult::pages_newly_deleted, LVRelState::pages_removed, palloc(), palloc0(), pfree(), pg_rusage_init(), pg_rusage_show(), pgstat_progress_end_command(), pgstat_progress_start_command(), pgstat_progress_update_param(), pgstat_report_vacuum(), pgStatBlockReadTime, pgStatBlockWriteTime, pgWalUsage, LVRelState::phase, LVRelState::pinskipped_pages, ErrorContextCallback::previous, PROGRESS_COMMAND_VACUUM, PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_FINAL_CLEANUP, pstrdup(), RelationData::rd_rel, LVRelState::rel, LVRelState::rel_pages, RelationGetNamespace, RelationGetRelationName, RelationGetRelid, LVRelState::relfrozenxid, LVRelState::relminmxid, LVRelState::relname, LVRelState::relnamespace, RowExclusiveLock, LVRelState::scanned_pages, should_attempt_truncation(), TimestampDifference(), TimestampDifferenceExceeds(), track_io_timing, TransactionIdPrecedesOrEquals(), VacuumParams::truncate, LVRelState::tuples_deleted, update_vacuum_error_info(), vac_close_indexes(), vac_open_indexes(), vac_update_relstats(), VACOPT_DISABLE_PAGE_SKIPPING, VACOPT_VERBOSE, VACOPTVALUE_AUTO, VACOPTVALUE_DISABLED, VACOPTVALUE_ENABLED, VACOPTVALUE_UNSPECIFIED, VACUUM_ERRCB_PHASE_TRUNCATE, VACUUM_ERRCB_PHASE_UNKNOWN, vacuum_error_callback(), vacuum_set_xid_limits(), VacuumPageDirty, VacuumPageHit, VacuumPageMiss, LVRelState::verbose, verbose, visibilitymap_count(), WalUsage::wal_bytes, WalUsage::wal_fpi, WalUsage::wal_records, and WalUsageAccumDiff().

lazy_check_needs_freeze()

static bool lazy_check_needs_freeze ( Buffer  buf, bool *  hastup, LVRelState *  vacrel  )

static

Definition at line 2297 of file vacuumlazy.c.

{
    Page        page = BufferGetPage(buf);
    OffsetNumber offnum,
                maxoff;
    HeapTupleHeader tupleheader;
 
    *hastup = false;
 
    /*
     * New and empty pages, obviously, don't contain tuples. We could make
     * sure that the page is registered in the FSM, but it doesn't seem worth
     * waiting for a cleanup lock just for that, especially because it's
     * likely that the pin holder will do so.
     */
    if (PageIsNew(page) || PageIsEmpty(page))
        return false;
 
    maxoff = PageGetMaxOffsetNumber(page);
    for (offnum = FirstOffsetNumber;
         offnum <= maxoff;
         offnum = OffsetNumberNext(offnum))
    {
        ItemId      itemid;
 
        /*
         * Set the offset number so that we can display it along with any
         * error that occurred while processing this tuple.
         */
        vacrel->offnum = offnum;
        itemid = PageGetItemId(page, offnum);
 
        /* this should match hastup test in count_nondeletable_pages() */
        if (ItemIdIsUsed(itemid))
            *hastup = true;
 
        /* dead and redirect items never need freezing */
        if (!ItemIdIsNormal(itemid))
            continue;
 
        tupleheader = (HeapTupleHeader) PageGetItem(page, itemid);
 
        if (heap_tuple_needs_freeze(tupleheader, vacrel->FreezeLimit,
                                    vacrel->MultiXactCutoff, buf))
            break;
    }                           /* scan along page */
 
    /* Clear the offset information once we have processed the given page. */
    vacrel->offnum = InvalidOffsetNumber;
 
    return (offnum <= maxoff);
}

References buf, BufferGetPage, FirstOffsetNumber, LVRelState::FreezeLimit, heap_tuple_needs_freeze(), InvalidOffsetNumber, ItemIdIsNormal, ItemIdIsUsed, LVRelState::MultiXactCutoff, LVRelState::offnum, OffsetNumberNext, PageGetItem, PageGetItemId, PageGetMaxOffsetNumber, PageIsEmpty, and PageIsNew.

Referenced by lazy_scan_heap().

lazy_check_wraparound_failsafe()

static bool lazy_check_wraparound_failsafe ( LVRelState *  vacrel )

static

Definition at line 2363 of file vacuumlazy.c.

{
    /* Don't warn more than once per VACUUM */
    if (vacrel->failsafe_active)
        return true;
 
    if (unlikely(vacuum_xid_failsafe_check(vacrel->relfrozenxid,
                                           vacrel->relminmxid)))
    {
        vacrel->failsafe_active = true;
 
        /* Disable index vacuuming, index cleanup, and heap rel truncation */
        vacrel->do_index_vacuuming = false;
        vacrel->do_index_cleanup = false;
        vacrel->do_rel_truncate = false;
 
        ereport(WARNING,
                (errmsg("bypassing nonessential maintenance of table \"%s.%s.%s\" as a failsafe after %d index scans",
                        get_database_name(MyDatabaseId),
                        vacrel->relnamespace,
                        vacrel->relname,
                        vacrel->num_index_scans),
                 errdetail("The table's relfrozenxid or relminmxid is too far in the past."),
                 errhint("Consider increasing configuration parameter \"maintenance_work_mem\" or \"autovacuum_work_mem\".\n"
                         "You might also need to consider other ways for VACUUM to keep up with the allocation of transaction IDs.")));
 
        /* Stop applying cost limits from this point on */
        VacuumCostActive = false;
        VacuumCostBalance = 0;
 
        return true;
    }
 
    return false;
}

References LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, LVRelState::do_rel_truncate, ereport, errdetail(), errhint(), errmsg(), LVRelState::failsafe_active, get_database_name(), MyDatabaseId, LVRelState::num_index_scans, LVRelState::relfrozenxid, LVRelState::relminmxid, LVRelState::relname, LVRelState::relnamespace, unlikely, vacuum_xid_failsafe_check(), VacuumCostActive, VacuumCostBalance, and WARNING.

Referenced by lazy_scan_heap(), and lazy_vacuum_all_indexes().

lazy_cleanup_all_indexes()

static void lazy_cleanup_all_indexes ( LVRelState *  vacrel )

static

Definition at line 2403 of file vacuumlazy.c.

{
    Assert(vacrel->nindexes > 0);
 
    /* Report that we are now cleaning up indexes */
    pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                 PROGRESS_VACUUM_PHASE_INDEX_CLEANUP);
 
    if (!ParallelVacuumIsActive(vacrel))
    {
        double      reltuples = vacrel->new_rel_tuples;
        bool        estimated_count =
        vacrel->tupcount_pages < vacrel->rel_pages;
 
        for (int idx = 0; idx < vacrel->nindexes; idx++)
        {
            Relation    indrel = vacrel->indrels[idx];
            IndexBulkDeleteResult *istat = vacrel->indstats[idx];
 
            vacrel->indstats[idx] =
                lazy_cleanup_one_index(indrel, istat, reltuples,
                                       estimated_count, vacrel);
        }
    }
    else
    {
        /* Outsource everything to parallel variant */
        parallel_vacuum_cleanup_all_indexes(vacrel->pvs, vacrel->new_rel_tuples,
                                            vacrel->num_index_scans,
                                            (vacrel->tupcount_pages < vacrel->rel_pages));
    }
}

References Assert(), idx(), LVRelState::indrels, LVRelState::indstats, lazy_cleanup_one_index(), LVRelState::new_rel_tuples, LVRelState::nindexes, LVRelState::num_index_scans, parallel_vacuum_cleanup_all_indexes(), ParallelVacuumIsActive, pgstat_progress_update_param(), PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_INDEX_CLEANUP, LVRelState::pvs, LVRelState::rel_pages, and LVRelState::tupcount_pages.

Referenced by lazy_scan_heap().

lazy_cleanup_one_index()

static IndexBulkDeleteResult * lazy_cleanup_one_index ( Relation  indrel, IndexBulkDeleteResult *  istat, double  reltuples, bool  estimated_count, LVRelState *  vacrel  )

static

Definition at line 2497 of file vacuumlazy.c.

{
    IndexVacuumInfo ivinfo;
    LVSavedErrInfo saved_err_info;
 
    ivinfo.index = indrel;
    ivinfo.analyze_only = false;
    ivinfo.report_progress = false;
    ivinfo.estimated_count = estimated_count;
    ivinfo.message_level = DEBUG2;
 
    ivinfo.num_heap_tuples = reltuples;
    ivinfo.strategy = vacrel->bstrategy;
 
    /*
     * Update error traceback information.
     *
     * The index name is saved during this phase and restored immediately
     * after this phase.  See vacuum_error_callback.
     */
    Assert(vacrel->indname == NULL);
    vacrel->indname = pstrdup(RelationGetRelationName(indrel));
    update_vacuum_error_info(vacrel, &saved_err_info,
                             VACUUM_ERRCB_PHASE_INDEX_CLEANUP,
                             InvalidBlockNumber, InvalidOffsetNumber);
 
    istat = vac_cleanup_one_index(&ivinfo, istat);
 
    /* Revert to the previous phase information for error traceback */
    restore_vacuum_error_info(vacrel, &saved_err_info);
    pfree(vacrel->indname);
    vacrel->indname = NULL;
 
    return istat;
}

References IndexVacuumInfo::analyze_only, Assert(), LVRelState::bstrategy, DEBUG2, IndexVacuumInfo::estimated_count, IndexVacuumInfo::index, LVRelState::indname, InvalidBlockNumber, InvalidOffsetNumber, IndexVacuumInfo::message_level, IndexVacuumInfo::num_heap_tuples, pfree(), pstrdup(), RelationGetRelationName, IndexVacuumInfo::report_progress, restore_vacuum_error_info(), IndexVacuumInfo::strategy, update_vacuum_error_info(), vac_cleanup_one_index(), and VACUUM_ERRCB_PHASE_INDEX_CLEANUP.

Referenced by lazy_cleanup_all_indexes().

lazy_scan_heap()

static void lazy_scan_heap ( LVRelState *  vacrel, VacuumParams *  params, bool  aggressive  )

static

Definition at line 740 of file vacuumlazy.c.

{
    VacDeadItems *dead_items;
    BlockNumber nblocks,
                blkno,
                next_unskippable_block,
                next_failsafe_block,
                next_fsm_block_to_vacuum;
    Buffer      vmbuffer = InvalidBuffer;
    bool        skipping_blocks;
    const int   initprog_index[] = {
        PROGRESS_VACUUM_PHASE,
        PROGRESS_VACUUM_TOTAL_HEAP_BLKS,
        PROGRESS_VACUUM_MAX_DEAD_TUPLES
    };
    int64       initprog_val[3];
    GlobalVisState *vistest;
 
    nblocks = RelationGetNumberOfBlocks(vacrel->rel);
    next_unskippable_block = 0;
    next_failsafe_block = 0;
    next_fsm_block_to_vacuum = 0;
    vacrel->rel_pages = nblocks;
    vacrel->scanned_pages = 0;
    vacrel->pinskipped_pages = 0;
    vacrel->frozenskipped_pages = 0;
    vacrel->tupcount_pages = 0;
    vacrel->pages_removed = 0;
    vacrel->lpdead_item_pages = 0;
    vacrel->nonempty_pages = 0;
 
    /* Initialize instrumentation counters */
    vacrel->num_index_scans = 0;
    vacrel->tuples_deleted = 0;
    vacrel->lpdead_items = 0;
    vacrel->new_dead_tuples = 0;
    vacrel->num_tuples = 0;
    vacrel->live_tuples = 0;
 
    vistest = GlobalVisTestFor(vacrel->rel);
 
    vacrel->indstats = (IndexBulkDeleteResult **)
        palloc0(vacrel->nindexes * sizeof(IndexBulkDeleteResult *));
 
    /*
     * Do failsafe precheck before calling dead_items_alloc.  This ensures
     * that parallel VACUUM won't be attempted when relfrozenxid is already
     * dangerously old.
     */
    lazy_check_wraparound_failsafe(vacrel);
 
    /*
     * Allocate the space for dead_items.  Note that this handles parallel
     * VACUUM initialization as part of allocating shared memory space used
     * for dead_items.
     */
    dead_items_alloc(vacrel, params->nworkers);
    dead_items = vacrel->dead_items;
 
    /* Report that we're scanning the heap, advertising total # of blocks */
    initprog_val[0] = PROGRESS_VACUUM_PHASE_SCAN_HEAP;
    initprog_val[1] = nblocks;
    initprog_val[2] = dead_items->max_items;
    pgstat_progress_update_multi_param(3, initprog_index, initprog_val);
 
    /*
     * Except when aggressive is set, we want to skip pages that are
     * all-visible according to the visibility map, but only when we can skip
     * at least SKIP_PAGES_THRESHOLD consecutive pages.  Since we're reading
     * sequentially, the OS should be doing readahead for us, so there's no
     * gain in skipping a page now and then; that's likely to disable
     * readahead and so be counterproductive. Also, skipping even a single
     * page means that we can't update relfrozenxid, so we only want to do it
     * if we can skip a goodly number of pages.
     *
     * When aggressive is set, we can't skip pages just because they are
     * all-visible, but we can still skip pages that are all-frozen, since
     * such pages do not need freezing and do not affect the value that we can
     * safely set for relfrozenxid or relminmxid.
     *
     * Before entering the main loop, establish the invariant that
     * next_unskippable_block is the next block number >= blkno that we can't
     * skip based on the visibility map, either all-visible for a regular scan
     * or all-frozen for an aggressive scan.  We set it to nblocks if there's
     * no such block.  We also set up the skipping_blocks flag correctly at
     * this stage.
     *
     * Note: The value returned by visibilitymap_get_status could be slightly
     * out-of-date, since we make this test before reading the corresponding
     * heap page or locking the buffer.  This is OK.  If we mistakenly think
     * that the page is all-visible or all-frozen when in fact the flag's just
     * been cleared, we might fail to vacuum the page.  It's easy to see that
     * skipping a page when aggressive is not set is not a very big deal; we
     * might leave some dead tuples lying around, but the next vacuum will
     * find them.  But even when aggressive *is* set, it's still OK if we miss
     * a page whose all-frozen marking has just been cleared.  Any new XIDs
     * just added to that page are necessarily newer than the GlobalXmin we
     * computed, so they'll have no effect on the value to which we can safely
     * set relfrozenxid.  A similar argument applies for MXIDs and relminmxid.
     *
     * We will scan the table's last page, at least to the extent of
     * determining whether it has tuples or not, even if it should be skipped
     * according to the above rules; except when we've already determined that
     * it's not worth trying to truncate the table.  This avoids having
     * lazy_truncate_heap() take access-exclusive lock on the table to attempt
     * a truncation that just fails immediately because there are tuples in
     * the last page.  This is worth avoiding mainly because such a lock must
     * be replayed on any hot standby, where it can be disruptive.
     */
    if ((params->options & VACOPT_DISABLE_PAGE_SKIPPING) == 0)
    {
        while (next_unskippable_block < nblocks)
        {
            uint8       vmstatus;
 
            vmstatus = visibilitymap_get_status(vacrel->rel,
                                                next_unskippable_block,
                                                &vmbuffer);
            if (aggressive)
            {
                if ((vmstatus & VISIBILITYMAP_ALL_FROZEN) == 0)
                    break;
            }
            else
            {
                if ((vmstatus & VISIBILITYMAP_ALL_VISIBLE) == 0)
                    break;
            }
            vacuum_delay_point();
            next_unskippable_block++;
        }
    }
 
    if (next_unskippable_block >= SKIP_PAGES_THRESHOLD)
        skipping_blocks = true;
    else
        skipping_blocks = false;
 
    for (blkno = 0; blkno < nblocks; blkno++)
    {
        Buffer      buf;
        Page        page;
        bool        all_visible_according_to_vm = false;
        LVPagePruneState prunestate;
 
        /*
         * Consider need to skip blocks.  See note above about forcing
         * scanning of last page.
         */
#define FORCE_CHECK_PAGE() \
        (blkno == nblocks - 1 && should_attempt_truncation(vacrel))
 
        pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_SCANNED, blkno);
 
        update_vacuum_error_info(vacrel, NULL, VACUUM_ERRCB_PHASE_SCAN_HEAP,
                                 blkno, InvalidOffsetNumber);
 
        if (blkno == next_unskippable_block)
        {
            /* Time to advance next_unskippable_block */
            next_unskippable_block++;
            if ((params->options & VACOPT_DISABLE_PAGE_SKIPPING) == 0)
            {
                while (next_unskippable_block < nblocks)
                {
                    uint8       vmskipflags;
 
                    vmskipflags = visibilitymap_get_status(vacrel->rel,
                                                           next_unskippable_block,
                                                           &vmbuffer);
                    if (aggressive)
                    {
                        if ((vmskipflags & VISIBILITYMAP_ALL_FROZEN) == 0)
                            break;
                    }
                    else
                    {
                        if ((vmskipflags & VISIBILITYMAP_ALL_VISIBLE) == 0)
                            break;
                    }
                    vacuum_delay_point();
                    next_unskippable_block++;
                }
            }
 
            /*
             * We know we can't skip the current block.  But set up
             * skipping_blocks to do the right thing at the following blocks.
             */
            if (next_unskippable_block - blkno > SKIP_PAGES_THRESHOLD)
                skipping_blocks = true;
            else
                skipping_blocks = false;
 
            /*
             * Normally, the fact that we can't skip this block must mean that
             * it's not all-visible.  But in an aggressive vacuum we know only
             * that it's not all-frozen, so it might still be all-visible.
             */
            if (aggressive && VM_ALL_VISIBLE(vacrel->rel, blkno, &vmbuffer))
                all_visible_according_to_vm = true;
        }
        else
        {
            /*
             * The current block is potentially skippable; if we've seen a
             * long enough run of skippable blocks to justify skipping it, and
             * we're not forced to check it, then go ahead and skip.
             * Otherwise, the page must be at least all-visible if not
             * all-frozen, so we can set all_visible_according_to_vm = true.
             */
            if (skipping_blocks && !FORCE_CHECK_PAGE())
            {
                /*
                 * Tricky, tricky.  If this is in aggressive vacuum, the page
                 * must have been all-frozen at the time we checked whether it
                 * was skippable, but it might not be any more.  We must be
                 * careful to count it as a skipped all-frozen page in that
                 * case, or else we'll think we can't update relfrozenxid and
                 * relminmxid.  If it's not an aggressive vacuum, we don't
                 * know whether it was all-frozen, so we have to recheck; but
                 * in this case an approximate answer is OK.
                 */
                if (aggressive || VM_ALL_FROZEN(vacrel->rel, blkno, &vmbuffer))
                    vacrel->frozenskipped_pages++;
                continue;
            }
            all_visible_according_to_vm = true;
        }
 
        vacuum_delay_point();
 
        /*
         * Regularly check if wraparound failsafe should trigger.
         *
         * There is a similar check inside lazy_vacuum_all_indexes(), but
         * relfrozenxid might start to look dangerously old before we reach
         * that point.  This check also provides failsafe coverage for the
         * one-pass strategy, and the two-pass strategy with the index_cleanup
         * param set to 'off'.
         */
        if (blkno - next_failsafe_block >= FAILSAFE_EVERY_PAGES)
        {
            lazy_check_wraparound_failsafe(vacrel);
            next_failsafe_block = blkno;
        }
 
        /*
         * Consider if we definitely have enough space to process TIDs on page
         * already.  If we are close to overrunning the available space for
         * dead_items TIDs, pause and do a cycle of vacuuming before we tackle
         * this page.
         */
        Assert(dead_items->max_items >= MaxHeapTuplesPerPage);
        if (dead_items->max_items - dead_items->num_items < MaxHeapTuplesPerPage)
        {
            /*
             * Before beginning index vacuuming, we release any pin we may
             * hold on the visibility map page.  This isn't necessary for
             * correctness, but we do it anyway to avoid holding the pin
             * across a lengthy, unrelated operation.
             */
            if (BufferIsValid(vmbuffer))
            {
                ReleaseBuffer(vmbuffer);
                vmbuffer = InvalidBuffer;
            }
 
            /* Perform a round of index and heap vacuuming */
            vacrel->consider_bypass_optimization = false;
            lazy_vacuum(vacrel);
 
            /*
             * Vacuum the Free Space Map to make newly-freed space visible on
             * upper-level FSM pages.  Note we have not yet processed blkno.
             */
            FreeSpaceMapVacuumRange(vacrel->rel, next_fsm_block_to_vacuum,
                                    blkno);
            next_fsm_block_to_vacuum = blkno;
 
            /* Report that we are once again scanning the heap */
            pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                         PROGRESS_VACUUM_PHASE_SCAN_HEAP);
        }
 
        /*
         * Set up visibility map page as needed.
         *
         * Pin the visibility map page in case we need to mark the page
         * all-visible.  In most cases this will be very cheap, because we'll
         * already have the correct page pinned anyway.  However, it's
         * possible that (a) next_unskippable_block is covered by a different
         * VM page than the current block or (b) we released our pin and did a
         * cycle of index vacuuming.
         */
        visibilitymap_pin(vacrel->rel, blkno, &vmbuffer);
 
        buf = ReadBufferExtended(vacrel->rel, MAIN_FORKNUM, blkno,
                                 RBM_NORMAL, vacrel->bstrategy);
 
        /*
         * We need buffer cleanup lock so that we can prune HOT chains and
         * defragment the page.
         */
        if (!ConditionalLockBufferForCleanup(buf))
        {
            bool        hastup;
 
            /*
             * If we're not performing an aggressive scan to guard against XID
             * wraparound, and we don't want to forcibly check the page, then
             * it's OK to skip vacuuming pages we get a lock conflict on. They
             * will be dealt with in some future vacuum.
             */
            if (!aggressive && !FORCE_CHECK_PAGE())
            {
                ReleaseBuffer(buf);
                vacrel->pinskipped_pages++;
                continue;
            }
 
            /*
             * Read the page with share lock to see if any xids on it need to
             * be frozen.  If not we just skip the page, after updating our
             * scan statistics.  If there are some, we wait for cleanup lock.
             *
             * We could defer the lock request further by remembering the page
             * and coming back to it later, or we could even register
             * ourselves for multiple buffers and then service whichever one
             * is received first.  For now, this seems good enough.
             *
             * If we get here with aggressive false, then we're just forcibly
             * checking the page, and so we don't want to insist on getting
             * the lock; we only need to know if the page contains tuples, so
             * that we can update nonempty_pages correctly.  It's convenient
             * to use lazy_check_needs_freeze() for both situations, though.
             */
            LockBuffer(buf, BUFFER_LOCK_SHARE);
            if (!lazy_check_needs_freeze(buf, &hastup, vacrel))
            {
                UnlockReleaseBuffer(buf);
                vacrel->scanned_pages++;
                vacrel->pinskipped_pages++;
                if (hastup)
                    vacrel->nonempty_pages = blkno + 1;
                continue;
            }
            if (!aggressive)
            {
                /*
                 * Here, we must not advance scanned_pages; that would amount
                 * to claiming that the page contains no freezable tuples.
                 */
                UnlockReleaseBuffer(buf);
                vacrel->pinskipped_pages++;
                if (hastup)
                    vacrel->nonempty_pages = blkno + 1;
                continue;
            }
            LockBuffer(buf, BUFFER_LOCK_UNLOCK);
            LockBufferForCleanup(buf);
            /* drop through to normal processing */
        }
 
        /*
         * By here we definitely have enough dead_items space for whatever
         * LP_DEAD tids are on this page, we have the visibility map page set
         * up in case we need to set this page's all_visible/all_frozen bit,
         * and we have a cleanup lock.  Any tuples on this page are now sure
         * to be "counted" by this VACUUM.
         *
         * One last piece of preamble needs to take place before we can prune:
         * we need to consider new and empty pages.
         */
        vacrel->scanned_pages++;
        vacrel->tupcount_pages++;
 
        page = BufferGetPage(buf);
 
        if (PageIsNew(page))
        {
            /*
             * All-zeroes pages can be left over if either a backend extends
             * the relation by a single page, but crashes before the newly
             * initialized page has been written out, or when bulk-extending
             * the relation (which creates a number of empty pages at the tail
             * end of the relation, but enters them into the FSM).
             *
             * Note we do not enter the page into the visibilitymap. That has
             * the downside that we repeatedly visit this page in subsequent
             * vacuums, but otherwise we'll never not discover the space on a
             * promoted standby. The harm of repeated checking ought to
             * normally not be too bad - the space usually should be used at
             * some point, otherwise there wouldn't be any regular vacuums.
             *
             * Make sure these pages are in the FSM, to ensure they can be
             * reused. Do that by testing if there's any space recorded for
             * the page. If not, enter it. We do so after releasing the lock
             * on the heap page, the FSM is approximate, after all.
             */
            UnlockReleaseBuffer(buf);
 
            if (GetRecordedFreeSpace(vacrel->rel, blkno) == 0)
            {
                Size        freespace = BLCKSZ - SizeOfPageHeaderData;
 
                RecordPageWithFreeSpace(vacrel->rel, blkno, freespace);
            }
            continue;
        }
 
        if (PageIsEmpty(page))
        {
            Size        freespace = PageGetHeapFreeSpace(page);
 
            /*
             * Empty pages are always all-visible and all-frozen (note that
             * the same is currently not true for new pages, see above).
             */
            if (!PageIsAllVisible(page))
            {
                START_CRIT_SECTION();
 
                /* mark buffer dirty before writing a WAL record */
                MarkBufferDirty(buf);
 
                /*
                 * It's possible that another backend has extended the heap,
                 * initialized the page, and then failed to WAL-log the page
                 * due to an ERROR.  Since heap extension is not WAL-logged,
                 * recovery might try to replay our record setting the page
                 * all-visible and find that the page isn't initialized, which
                 * will cause a PANIC.  To prevent that, check whether the
                 * page has been previously WAL-logged, and if not, do that
                 * now.
                 */
                if (RelationNeedsWAL(vacrel->rel) &&
                    PageGetLSN(page) == InvalidXLogRecPtr)
                    log_newpage_buffer(buf, true);
 
                PageSetAllVisible(page);
                visibilitymap_set(vacrel->rel, blkno, buf, InvalidXLogRecPtr,
                                  vmbuffer, InvalidTransactionId,
                                  VISIBILITYMAP_ALL_VISIBLE | VISIBILITYMAP_ALL_FROZEN);
                END_CRIT_SECTION();
            }
 
            UnlockReleaseBuffer(buf);
            RecordPageWithFreeSpace(vacrel->rel, blkno, freespace);
            continue;
        }
 
        /*
         * Prune and freeze tuples.
         *
         * Accumulates details of remaining LP_DEAD line pointers on page in
         * dead_items array.  This includes LP_DEAD line pointers that we
         * pruned ourselves, as well as existing LP_DEAD line pointers that
         * were pruned some time earlier.  Also considers freezing XIDs in the
         * tuple headers of remaining items with storage.
         */
        lazy_scan_prune(vacrel, buf, blkno, page, vistest, &prunestate);
 
        Assert(!prunestate.all_visible || !prunestate.has_lpdead_items);
 
        /* Remember the location of the last page with nonremovable tuples */
        if (prunestate.hastup)
            vacrel->nonempty_pages = blkno + 1;
 
        if (vacrel->nindexes == 0)
        {
            /*
             * Consider the need to do page-at-a-time heap vacuuming when
             * using the one-pass strategy now.
             *
             * The one-pass strategy will never call lazy_vacuum().  The steps
             * performed here can be thought of as the one-pass equivalent of
             * a call to lazy_vacuum().
             */
            if (prunestate.has_lpdead_items)
            {
                Size        freespace;
 
                lazy_vacuum_heap_page(vacrel, blkno, buf, 0, &vmbuffer);
 
                /* Forget the LP_DEAD items that we just vacuumed */
                dead_items->num_items = 0;
 
                /*
                 * Periodically perform FSM vacuuming to make newly-freed
                 * space visible on upper FSM pages.  Note we have not yet
                 * performed FSM processing for blkno.
                 */
                if (blkno - next_fsm_block_to_vacuum >= VACUUM_FSM_EVERY_PAGES)
                {
                    FreeSpaceMapVacuumRange(vacrel->rel, next_fsm_block_to_vacuum,
                                            blkno);
                    next_fsm_block_to_vacuum = blkno;
                }
 
                /*
                 * Now perform FSM processing for blkno, and move on to next
                 * page.
                 *
                 * Our call to lazy_vacuum_heap_page() will have considered if
                 * it's possible to set all_visible/all_frozen independently
                 * of lazy_scan_prune().  Note that prunestate was invalidated
                 * by lazy_vacuum_heap_page() call.
                 */
                freespace = PageGetHeapFreeSpace(page);
 
                UnlockReleaseBuffer(buf);
                RecordPageWithFreeSpace(vacrel->rel, blkno, freespace);
                continue;
            }
 
            /*
             * There was no call to lazy_vacuum_heap_page() because pruning
             * didn't encounter/create any LP_DEAD items that needed to be
             * vacuumed.  Prune state has not been invalidated, so proceed
             * with prunestate-driven visibility map and FSM steps (just like
             * the two-pass strategy).
             */
            Assert(dead_items->num_items == 0);
        }
 
        /*
         * Handle setting visibility map bit based on what the VM said about
         * the page before pruning started, and using prunestate
         */
        if (!all_visible_according_to_vm && prunestate.all_visible)
        {
            uint8       flags = VISIBILITYMAP_ALL_VISIBLE;
 
            if (prunestate.all_frozen)
                flags |= VISIBILITYMAP_ALL_FROZEN;
 
            /*
             * It should never be the case that the visibility map page is set
             * while the page-level bit is clear, but the reverse is allowed
             * (if checksums are not enabled).  Regardless, set both bits so
             * that we get back in sync.
             *
             * NB: If the heap page is all-visible but the VM bit is not set,
             * we don't need to dirty the heap page.  However, if checksums
             * are enabled, we do need to make sure that the heap page is
             * dirtied before passing it to visibilitymap_set(), because it
             * may be logged.  Given that this situation should only happen in
             * rare cases after a crash, it is not worth optimizing.
             */
            PageSetAllVisible(page);
            MarkBufferDirty(buf);
            visibilitymap_set(vacrel->rel, blkno, buf, InvalidXLogRecPtr,
                              vmbuffer, prunestate.visibility_cutoff_xid,
                              flags);
        }
 
        /*
         * As of PostgreSQL 9.2, the visibility map bit should never be set if
         * the page-level bit is clear.  However, it's possible that the bit
         * got cleared after we checked it and before we took the buffer
         * content lock, so we must recheck before jumping to the conclusion
         * that something bad has happened.
         */
        else if (all_visible_according_to_vm && !PageIsAllVisible(page)
                 && VM_ALL_VISIBLE(vacrel->rel, blkno, &vmbuffer))
        {
            elog(WARNING, "page is not marked all-visible but visibility map bit is set in relation \"%s\" page %u",
                 vacrel->relname, blkno);
            visibilitymap_clear(vacrel->rel, blkno, vmbuffer,
                                VISIBILITYMAP_VALID_BITS);
        }
 
        /*
         * It's possible for the value returned by
         * GetOldestNonRemovableTransactionId() to move backwards, so it's not
         * wrong for us to see tuples that appear to not be visible to
         * everyone yet, while PD_ALL_VISIBLE is already set. The real safe
         * xmin value never moves backwards, but
         * GetOldestNonRemovableTransactionId() is conservative and sometimes
         * returns a value that's unnecessarily small, so if we see that
         * contradiction it just means that the tuples that we think are not
         * visible to everyone yet actually are, and the PD_ALL_VISIBLE flag
         * is correct.
         *
         * There should never be LP_DEAD items on a page with PD_ALL_VISIBLE
         * set, however.
         */
        else if (prunestate.has_lpdead_items && PageIsAllVisible(page))
        {
            elog(WARNING, "page containing LP_DEAD items is marked as all-visible in relation \"%s\" page %u",
                 vacrel->relname, blkno);
            PageClearAllVisible(page);
            MarkBufferDirty(buf);
            visibilitymap_clear(vacrel->rel, blkno, vmbuffer,
                                VISIBILITYMAP_VALID_BITS);
        }
 
        /*
         * If the all-visible page is all-frozen but not marked as such yet,
         * mark it as all-frozen.  Note that all_frozen is only valid if
         * all_visible is true, so we must check both.
         */
        else if (all_visible_according_to_vm && prunestate.all_visible &&
                 prunestate.all_frozen &&
                 !VM_ALL_FROZEN(vacrel->rel, blkno, &vmbuffer))
        {
            /*
             * We can pass InvalidTransactionId as the cutoff XID here,
             * because setting the all-frozen bit doesn't cause recovery
             * conflicts.
             */
            visibilitymap_set(vacrel->rel, blkno, buf, InvalidXLogRecPtr,
                              vmbuffer, InvalidTransactionId,
                              VISIBILITYMAP_ALL_FROZEN);
        }
 
        /*
         * Final steps for block: drop cleanup lock, record free space in the
         * FSM
         */
        if (prunestate.has_lpdead_items && vacrel->do_index_vacuuming)
        {
            /*
             * Wait until lazy_vacuum_heap_rel() to save free space.  This
             * doesn't just save us some cycles; it also allows us to record
             * any additional free space that lazy_vacuum_heap_page() will
             * make available in cases where it's possible to truncate the
             * page's line pointer array.
             *
             * Note: It's not in fact 100% certain that we really will call
             * lazy_vacuum_heap_rel() -- lazy_vacuum() might yet opt to skip
             * index vacuuming (and so must skip heap vacuuming).  This is
             * deemed okay because it only happens in emergencies, or when
             * there is very little free space anyway. (Besides, we start
             * recording free space in the FSM once index vacuuming has been
             * abandoned.)
             *
             * Note: The one-pass (no indexes) case is only supposed to make
             * it this far when there were no LP_DEAD items during pruning.
             */
            Assert(vacrel->nindexes > 0);
            UnlockReleaseBuffer(buf);
        }
        else
        {
            Size        freespace = PageGetHeapFreeSpace(page);
 
            UnlockReleaseBuffer(buf);
            RecordPageWithFreeSpace(vacrel->rel, blkno, freespace);
        }
    }
 
    /* report that everything is now scanned */
    pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_SCANNED, blkno);
 
    /* Clear the block number information */
    vacrel->blkno = InvalidBlockNumber;
 
    /* now we can compute the new value for pg_class.reltuples */
    vacrel->new_live_tuples = vac_estimate_reltuples(vacrel->rel, nblocks,
                                                     vacrel->tupcount_pages,
                                                     vacrel->live_tuples);
 
    /*
     * Also compute the total number of surviving heap entries.  In the
     * (unlikely) scenario that new_live_tuples is -1, take it as zero.
     */
    vacrel->new_rel_tuples =
        Max(vacrel->new_live_tuples, 0) + vacrel->new_dead_tuples;
 
    /*
     * Release any remaining pin on visibility map page.
     */
    if (BufferIsValid(vmbuffer))
    {
        ReleaseBuffer(vmbuffer);
        vmbuffer = InvalidBuffer;
    }
 
    /* Perform a final round of index and heap vacuuming */
    if (dead_items->num_items > 0)
        lazy_vacuum(vacrel);
 
    /*
     * Vacuum the remainder of the Free Space Map.  We must do this whether or
     * not there were indexes, and whether or not we bypassed index vacuuming.
     */
    if (blkno > next_fsm_block_to_vacuum)
        FreeSpaceMapVacuumRange(vacrel->rel, next_fsm_block_to_vacuum, blkno);
 
    /* report all blocks vacuumed */
    pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_VACUUMED, blkno);
 
    /* Do post-vacuum cleanup */
    if (vacrel->nindexes > 0 && vacrel->do_index_cleanup)
        lazy_cleanup_all_indexes(vacrel);
 
    /*
     * Free resources managed by dead_items_alloc.  This will end parallel
     * mode when needed (it must end before updating index statistics as we
     * can't write in parallel mode).
     */
    dead_items_cleanup(vacrel);
 
    /* Update index statistics */
    if (vacrel->nindexes > 0 && vacrel->do_index_cleanup)
        update_index_statistics(vacrel);
}

References LVPagePruneState::all_frozen, LVPagePruneState::all_visible, Assert(), LVRelState::blkno, LVRelState::bstrategy, buf, BUFFER_LOCK_SHARE, BUFFER_LOCK_UNLOCK, BufferGetPage, BufferIsValid, ConditionalLockBufferForCleanup(), LVRelState::consider_bypass_optimization, LVRelState::dead_items, dead_items_alloc(), dead_items_cleanup(), LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, elog, END_CRIT_SECTION, FAILSAFE_EVERY_PAGES, FORCE_CHECK_PAGE, FreeSpaceMapVacuumRange(), LVRelState::frozenskipped_pages, GetRecordedFreeSpace(), GlobalVisTestFor(), LVPagePruneState::has_lpdead_items, LVPagePruneState::hastup, LVRelState::indstats, InvalidBlockNumber, InvalidBuffer, InvalidOffsetNumber, InvalidTransactionId, InvalidXLogRecPtr, lazy_check_needs_freeze(), lazy_check_wraparound_failsafe(), lazy_cleanup_all_indexes(), lazy_scan_prune(), lazy_vacuum(), lazy_vacuum_heap_page(), LVRelState::live_tuples, LockBuffer(), LockBufferForCleanup(), log_newpage_buffer(), LVRelState::lpdead_item_pages, LVRelState::lpdead_items, MAIN_FORKNUM, MarkBufferDirty(), Max, VacDeadItems::max_items, MaxHeapTuplesPerPage, LVRelState::new_dead_tuples, LVRelState::new_live_tuples, LVRelState::new_rel_tuples, LVRelState::nindexes, LVRelState::nonempty_pages, LVRelState::num_index_scans, VacDeadItems::num_items, LVRelState::num_tuples, VacuumParams::nworkers, VacuumParams::options, PageClearAllVisible, PageGetHeapFreeSpace(), PageGetLSN, PageIsAllVisible, PageIsEmpty, PageIsNew, LVRelState::pages_removed, PageSetAllVisible, palloc0(), pgstat_progress_update_multi_param(), pgstat_progress_update_param(), LVRelState::pinskipped_pages, PROGRESS_VACUUM_HEAP_BLKS_SCANNED, PROGRESS_VACUUM_HEAP_BLKS_VACUUMED, PROGRESS_VACUUM_MAX_DEAD_TUPLES, PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_SCAN_HEAP, PROGRESS_VACUUM_TOTAL_HEAP_BLKS, RBM_NORMAL, ReadBufferExtended(), RecordPageWithFreeSpace(), LVRelState::rel, LVRelState::rel_pages, RelationGetNumberOfBlocks, RelationNeedsWAL, ReleaseBuffer(), LVRelState::relname, LVRelState::scanned_pages, SizeOfPageHeaderData, SKIP_PAGES_THRESHOLD, START_CRIT_SECTION, LVRelState::tupcount_pages, LVRelState::tuples_deleted, UnlockReleaseBuffer(), update_index_statistics(), update_vacuum_error_info(), vac_estimate_reltuples(), VACOPT_DISABLE_PAGE_SKIPPING, vacuum_delay_point(), VACUUM_ERRCB_PHASE_SCAN_HEAP, VACUUM_FSM_EVERY_PAGES, LVPagePruneState::visibility_cutoff_xid, VISIBILITYMAP_ALL_FROZEN, VISIBILITYMAP_ALL_VISIBLE, visibilitymap_clear(), visibilitymap_get_status(), visibilitymap_pin(), visibilitymap_set(), VISIBILITYMAP_VALID_BITS, VM_ALL_FROZEN, VM_ALL_VISIBLE, and WARNING.

Referenced by heap_vacuum_rel().

lazy_scan_prune()

static void lazy_scan_prune ( LVRelState *  vacrel, Buffer  buf, BlockNumber  blkno, Page  page, GlobalVisState *  vistest, LVPagePruneState *  prunestate  )

static

Definition at line 1471 of file vacuumlazy.c.

{
    Relation    rel = vacrel->rel;
    OffsetNumber offnum,
                maxoff;
    ItemId      itemid;
    HeapTupleData tuple;
    HTSV_Result res;
    int         tuples_deleted,
                lpdead_items,
                new_dead_tuples,
                num_tuples,
                live_tuples;
    int         nnewlpdead;
    int         nfrozen;
    OffsetNumber deadoffsets[MaxHeapTuplesPerPage];
    xl_heap_freeze_tuple frozen[MaxHeapTuplesPerPage];
 
    maxoff = PageGetMaxOffsetNumber(page);
 
retry:
 
    /* Initialize (or reset) page-level counters */
    tuples_deleted = 0;
    lpdead_items = 0;
    new_dead_tuples = 0;
    num_tuples = 0;
    live_tuples = 0;
 
    /*
     * Prune all HOT-update chains in this page.
     *
     * We count tuples removed by the pruning step as tuples_deleted.  Its
     * final value can be thought of as the number of tuples that have been
     * deleted from the table.  It should not be confused with lpdead_items;
     * lpdead_items's final value can be thought of as the number of tuples
     * that were deleted from indexes.
     */
    tuples_deleted = heap_page_prune(rel, buf, vistest,
                                     InvalidTransactionId, 0, &nnewlpdead,
                                     &vacrel->offnum);
 
    /*
     * Now scan the page to collect LP_DEAD items and check for tuples
     * requiring freezing among remaining tuples with storage
     */
    prunestate->hastup = false;
    prunestate->has_lpdead_items = false;
    prunestate->all_visible = true;
    prunestate->all_frozen = true;
    prunestate->visibility_cutoff_xid = InvalidTransactionId;
    nfrozen = 0;
 
    for (offnum = FirstOffsetNumber;
         offnum <= maxoff;
         offnum = OffsetNumberNext(offnum))
    {
        bool        tuple_totally_frozen;
 
        /*
         * Set the offset number so that we can display it along with any
         * error that occurred while processing this tuple.
         */
        vacrel->offnum = offnum;
        itemid = PageGetItemId(page, offnum);
 
        if (!ItemIdIsUsed(itemid))
            continue;
 
        /* Redirect items mustn't be touched */
        if (ItemIdIsRedirected(itemid))
        {
            prunestate->hastup = true;  /* page won't be truncatable */
            continue;
        }
 
        /*
         * LP_DEAD items are processed outside of the loop.
         *
         * Note that we deliberately don't set hastup=true in the case of an
         * LP_DEAD item here, which is not how lazy_check_needs_freeze() or
         * count_nondeletable_pages() do it -- they only consider pages empty
         * when they only have LP_UNUSED items, which is important for
         * correctness.
         *
         * Our assumption is that any LP_DEAD items we encounter here will
         * become LP_UNUSED inside lazy_vacuum_heap_page() before we actually
         * call count_nondeletable_pages().  In any case our opinion of
         * whether or not a page 'hastup' (which is how our caller sets its
         * vacrel->nonempty_pages value) is inherently race-prone.  It must be
         * treated as advisory/unreliable, so we might as well be slightly
         * optimistic.
         */
        if (ItemIdIsDead(itemid))
        {
            deadoffsets[lpdead_items++] = offnum;
            prunestate->all_visible = false;
            prunestate->has_lpdead_items = true;
            continue;
        }
 
        Assert(ItemIdIsNormal(itemid));
 
        ItemPointerSet(&(tuple.t_self), blkno, offnum);
        tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
        tuple.t_len = ItemIdGetLength(itemid);
        tuple.t_tableOid = RelationGetRelid(rel);
 
        /*
         * DEAD tuples are almost always pruned into LP_DEAD line pointers by
         * heap_page_prune(), but it's possible that the tuple state changed
         * since heap_page_prune() looked.  Handle that here by restarting.
         * (See comments at the top of function for a full explanation.)
         */
        res = HeapTupleSatisfiesVacuum(&tuple, vacrel->OldestXmin, buf);
 
        if (unlikely(res == HEAPTUPLE_DEAD))
            goto retry;
 
        /*
         * The criteria for counting a tuple as live in this block need to
         * match what analyze.c's acquire_sample_rows() does, otherwise VACUUM
         * and ANALYZE may produce wildly different reltuples values, e.g.
         * when there are many recently-dead tuples.
         *
         * The logic here is a bit simpler than acquire_sample_rows(), as
         * VACUUM can't run inside a transaction block, which makes some cases
         * impossible (e.g. in-progress insert from the same transaction).
         *
         * We treat LP_DEAD items (which are the closest thing to DEAD tuples
         * that might be seen here) differently, too: we assume that they'll
         * become LP_UNUSED before VACUUM finishes.  This difference is only
         * superficial.  VACUUM effectively agrees with ANALYZE about DEAD
         * items, in the end.  VACUUM won't remember LP_DEAD items, but only
         * because they're not supposed to be left behind when it is done.
         * (Cases where we bypass index vacuuming will violate this optimistic
         * assumption, but the overall impact of that should be negligible.)
         */
        switch (res)
        {
            case HEAPTUPLE_LIVE:
 
                /*
                 * Count it as live.  Not only is this natural, but it's also
                 * what acquire_sample_rows() does.
                 */
                live_tuples++;
 
                /*
                 * Is the tuple definitely visible to all transactions?
                 *
                 * NB: Like with per-tuple hint bits, we can't set the
                 * PD_ALL_VISIBLE flag if the inserter committed
                 * asynchronously. See SetHintBits for more info. Check that
                 * the tuple is hinted xmin-committed because of that.
                 */
                if (prunestate->all_visible)
                {
                    TransactionId xmin;
 
                    if (!HeapTupleHeaderXminCommitted(tuple.t_data))
                    {
                        prunestate->all_visible = false;
                        break;
                    }
 
                    /*
                     * The inserter definitely committed. But is it old enough
                     * that everyone sees it as committed?
                     */
                    xmin = HeapTupleHeaderGetXmin(tuple.t_data);
                    if (!TransactionIdPrecedes(xmin, vacrel->OldestXmin))
                    {
                        prunestate->all_visible = false;
                        break;
                    }
 
                    /* Track newest xmin on page. */
                    if (TransactionIdFollows(xmin, prunestate->visibility_cutoff_xid))
                        prunestate->visibility_cutoff_xid = xmin;
                }
                break;
            case HEAPTUPLE_RECENTLY_DEAD:
 
                /*
                 * If tuple is recently deleted then we must not remove it
                 * from relation.  (We only remove items that are LP_DEAD from
                 * pruning.)
                 */
                new_dead_tuples++;
                prunestate->all_visible = false;
                break;
            case HEAPTUPLE_INSERT_IN_PROGRESS:
 
                /*
                 * We do not count these rows as live, because we expect the
                 * inserting transaction to update the counters at commit, and
                 * we assume that will happen only after we report our
                 * results.  This assumption is a bit shaky, but it is what
                 * acquire_sample_rows() does, so be consistent.
                 */
                prunestate->all_visible = false;
                break;
            case HEAPTUPLE_DELETE_IN_PROGRESS:
                /* This is an expected case during concurrent vacuum */
                prunestate->all_visible = false;
 
                /*
                 * Count such rows as live.  As above, we assume the deleting
                 * transaction will commit and update the counters after we
                 * report.
                 */
                live_tuples++;
                break;
            default:
                elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
                break;
        }
 
        /*
         * Non-removable tuple (i.e. tuple with storage).
         *
         * Check tuple left behind after pruning to see if needs to be frozen
         * now.
         */
        num_tuples++;
        prunestate->hastup = true;
        if (heap_prepare_freeze_tuple(tuple.t_data,
                                      vacrel->relfrozenxid,
                                      vacrel->relminmxid,
                                      vacrel->FreezeLimit,
                                      vacrel->MultiXactCutoff,
                                      &frozen[nfrozen],
                                      &tuple_totally_frozen))
        {
            /* Will execute freeze below */
            frozen[nfrozen++].offset = offnum;
        }
 
        /*
         * If tuple is not frozen (and not about to become frozen) then caller
         * had better not go on to set this page's VM bit
         */
        if (!tuple_totally_frozen)
            prunestate->all_frozen = false;
    }
 
    /*
     * We have now divided every item on the page into either an LP_DEAD item
     * that will need to be vacuumed in indexes later, or a LP_NORMAL tuple
     * that remains and needs to be considered for freezing now (LP_UNUSED and
     * LP_REDIRECT items also remain, but are of no further interest to us).
     */
    vacrel->offnum = InvalidOffsetNumber;
 
    /*
     * Consider the need to freeze any items with tuple storage from the page
     * first (arbitrary)
     */
    if (nfrozen > 0)
    {
        Assert(prunestate->hastup);
 
        /*
         * At least one tuple with storage needs to be frozen -- execute that
         * now.
         *
         * If we need to freeze any tuples we'll mark the buffer dirty, and
         * write a WAL record recording the changes.  We must log the changes
         * to be crash-safe against future truncation of CLOG.
         */
        START_CRIT_SECTION();
 
        MarkBufferDirty(buf);
 
        /* execute collected freezes */
        for (int i = 0; i < nfrozen; i++)
        {
            HeapTupleHeader htup;
 
            itemid = PageGetItemId(page, frozen[i].offset);
            htup = (HeapTupleHeader) PageGetItem(page, itemid);
 
            heap_execute_freeze_tuple(htup, &frozen[i]);
        }
 
        /* Now WAL-log freezing if necessary */
        if (RelationNeedsWAL(vacrel->rel))
        {
            XLogRecPtr  recptr;
 
            recptr = log_heap_freeze(vacrel->rel, buf, vacrel->FreezeLimit,
                                     frozen, nfrozen);
            PageSetLSN(page, recptr);
        }
 
        END_CRIT_SECTION();
    }
 
    /*
     * The second pass over the heap can also set visibility map bits, using
     * the same approach.  This is important when the table frequently has a
     * few old LP_DEAD items on each page by the time we get to it (typically
     * because past opportunistic pruning operations freed some non-HOT
     * tuples).
     *
     * VACUUM will call heap_page_is_all_visible() during the second pass over
     * the heap to determine all_visible and all_frozen for the page -- this
     * is a specialized version of the logic from this function.  Now that
     * we've finished pruning and freezing, make sure that we're in total
     * agreement with heap_page_is_all_visible() using an assertion.
     */
#ifdef USE_ASSERT_CHECKING
    /* Note that all_frozen value does not matter when !all_visible */
    if (prunestate->all_visible)
    {
        TransactionId cutoff;
        bool        all_frozen;
 
        if (!heap_page_is_all_visible(vacrel, buf, &cutoff, &all_frozen))
            Assert(false);
 
        Assert(lpdead_items == 0);
        Assert(prunestate->all_frozen == all_frozen);
 
        /*
         * It's possible that we froze tuples and made the page's XID cutoff
         * (for recovery conflict purposes) FrozenTransactionId.  This is okay
         * because visibility_cutoff_xid will be logged by our caller in a
         * moment.
         */
        Assert(cutoff == FrozenTransactionId ||
               cutoff == prunestate->visibility_cutoff_xid);
    }
#endif
 
    /*
     * Now save details of the LP_DEAD items from the page in vacrel
     */
    if (lpdead_items > 0)
    {
        VacDeadItems *dead_items = vacrel->dead_items;
        ItemPointerData tmp;
 
        Assert(!prunestate->all_visible);
        Assert(prunestate->has_lpdead_items);
 
        vacrel->lpdead_item_pages++;
 
        ItemPointerSetBlockNumber(&tmp, blkno);
 
        for (int i = 0; i < lpdead_items; i++)
        {
            ItemPointerSetOffsetNumber(&tmp, deadoffsets[i]);
            dead_items->items[dead_items->num_items++] = tmp;
        }
 
        Assert(dead_items->num_items <= dead_items->max_items);
        pgstat_progress_update_param(PROGRESS_VACUUM_NUM_DEAD_TUPLES,
                                     dead_items->num_items);
    }
 
    /* Finally, add page-local counts to whole-VACUUM counts */
    vacrel->tuples_deleted += tuples_deleted;
    vacrel->lpdead_items += lpdead_items;
    vacrel->new_dead_tuples += new_dead_tuples;
    vacrel->num_tuples += num_tuples;
    vacrel->live_tuples += live_tuples;
}

References LVPagePruneState::all_frozen, LVPagePruneState::all_visible, Assert(), buf, LVRelState::dead_items, elog, END_CRIT_SECTION, ERROR, FirstOffsetNumber, LVRelState::FreezeLimit, FrozenTransactionId, LVPagePruneState::has_lpdead_items, LVPagePruneState::hastup, heap_execute_freeze_tuple(), heap_page_is_all_visible(), heap_page_prune(), heap_prepare_freeze_tuple(), HEAPTUPLE_DEAD, HEAPTUPLE_DELETE_IN_PROGRESS, HEAPTUPLE_INSERT_IN_PROGRESS, HEAPTUPLE_LIVE, HEAPTUPLE_RECENTLY_DEAD, HeapTupleHeaderGetXmin, HeapTupleHeaderXminCommitted, HeapTupleSatisfiesVacuum(), i, InvalidOffsetNumber, InvalidTransactionId, ItemIdGetLength, ItemIdIsDead, ItemIdIsNormal, ItemIdIsRedirected, ItemIdIsUsed, ItemPointerSet, ItemPointerSetBlockNumber, ItemPointerSetOffsetNumber, VacDeadItems::items, LVRelState::live_tuples, log_heap_freeze(), LVRelState::lpdead_item_pages, LVRelState::lpdead_items, MarkBufferDirty(), VacDeadItems::max_items, MaxHeapTuplesPerPage, LVRelState::MultiXactCutoff, LVRelState::new_dead_tuples, VacDeadItems::num_items, LVRelState::num_tuples, LVRelState::offnum, xl_heap_freeze_tuple::offset, OffsetNumberNext, LVRelState::OldestXmin, PageGetItem, PageGetItemId, PageGetMaxOffsetNumber, PageSetLSN, pgstat_progress_update_param(), PROGRESS_VACUUM_NUM_DEAD_TUPLES, LVRelState::rel, RelationGetRelid, RelationNeedsWAL, LVRelState::relfrozenxid, LVRelState::relminmxid, res, START_CRIT_SECTION, HeapTupleData::t_data, HeapTupleData::t_len, HeapTupleData::t_self, HeapTupleData::t_tableOid, TransactionIdFollows(), TransactionIdPrecedes(), LVRelState::tuples_deleted, unlikely, and LVPagePruneState::visibility_cutoff_xid.

Referenced by lazy_scan_heap().

lazy_truncate_heap()

static void lazy_truncate_heap ( LVRelState *  vacrel )

static

Definition at line 2578 of file vacuumlazy.c.

{
    BlockNumber orig_rel_pages = vacrel->rel_pages;
    BlockNumber new_rel_pages;
    bool        lock_waiter_detected;
    int         lock_retry;
 
    /* Report that we are now truncating */
    pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                 PROGRESS_VACUUM_PHASE_TRUNCATE);
 
    /*
     * Loop until no more truncating can be done.
     */
    do
    {
        /*
         * We need full exclusive lock on the relation in order to do
         * truncation. If we can't get it, give up rather than waiting --- we
         * don't want to block other backends, and we don't want to deadlock
         * (which is quite possible considering we already hold a lower-grade
         * lock).
         */
        lock_waiter_detected = false;
        lock_retry = 0;
        while (true)
        {
            if (ConditionalLockRelation(vacrel->rel, AccessExclusiveLock))
                break;
 
            /*
             * Check for interrupts while trying to (re-)acquire the exclusive
             * lock.
             */
            CHECK_FOR_INTERRUPTS();
 
            if (++lock_retry > (VACUUM_TRUNCATE_LOCK_TIMEOUT /
                                VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL))
            {
                /*
                 * We failed to establish the lock in the specified number of
                 * retries. This means we give up truncating.
                 */
                ereport(vacrel->verbose ? INFO : DEBUG2,
                        (errmsg("\"%s\": stopping truncate due to conflicting lock request",
                                vacrel->relname)));
                return;
            }
 
            (void) WaitLatch(MyLatch,
                             WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
                             VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL,
                             WAIT_EVENT_VACUUM_TRUNCATE);
            ResetLatch(MyLatch);
        }
 
        /*
         * Now that we have exclusive lock, look to see if the rel has grown
         * whilst we were vacuuming with non-exclusive lock.  If so, give up;
         * the newly added pages presumably contain non-deletable tuples.
         */
        new_rel_pages = RelationGetNumberOfBlocks(vacrel->rel);
        if (new_rel_pages != orig_rel_pages)
        {
            /*
             * Note: we intentionally don't update vacrel->rel_pages with the
             * new rel size here.  If we did, it would amount to assuming that
             * the new pages are empty, which is unlikely. Leaving the numbers
             * alone amounts to assuming that the new pages have the same
             * tuple density as existing ones, which is less unlikely.
             */
            UnlockRelation(vacrel->rel, AccessExclusiveLock);
            return;
        }
 
        /*
         * Scan backwards from the end to verify that the end pages actually
         * contain no tuples.  This is *necessary*, not optional, because
         * other backends could have added tuples to these pages whilst we
         * were vacuuming.
         */
        new_rel_pages = count_nondeletable_pages(vacrel, &lock_waiter_detected);
        vacrel->blkno = new_rel_pages;
 
        if (new_rel_pages >= orig_rel_pages)
        {
            /* can't do anything after all */
            UnlockRelation(vacrel->rel, AccessExclusiveLock);
            return;
        }
 
        /*
         * Okay to truncate.
         */
        RelationTruncate(vacrel->rel, new_rel_pages);
 
        /*
         * We can release the exclusive lock as soon as we have truncated.
         * Other backends can't safely access the relation until they have
         * processed the smgr invalidation that smgrtruncate sent out ... but
         * that should happen as part of standard invalidation processing once
         * they acquire lock on the relation.
         */
        UnlockRelation(vacrel->rel, AccessExclusiveLock);
 
        /*
         * Update statistics.  Here, it *is* correct to adjust rel_pages
         * without also touching reltuples, since the tuple count wasn't
         * changed by the truncation.
         */
        vacrel->pages_removed += orig_rel_pages - new_rel_pages;
        vacrel->rel_pages = new_rel_pages;
 
        ereport(vacrel->verbose ? INFO : DEBUG2,
                (errmsg("table \"%s\": truncated %u to %u pages",
                        vacrel->relname,
                        orig_rel_pages, new_rel_pages)));
        orig_rel_pages = new_rel_pages;
    } while (new_rel_pages > vacrel->nonempty_pages && lock_waiter_detected);
}

References AccessExclusiveLock, LVRelState::blkno, CHECK_FOR_INTERRUPTS, ConditionalLockRelation(), count_nondeletable_pages(), DEBUG2, ereport, errmsg(), INFO, MyLatch, LVRelState::nonempty_pages, LVRelState::pages_removed, pgstat_progress_update_param(), PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_TRUNCATE, LVRelState::rel, LVRelState::rel_pages, RelationGetNumberOfBlocks, RelationTruncate(), LVRelState::relname, ResetLatch(), UnlockRelation(), VACUUM_TRUNCATE_LOCK_TIMEOUT, VACUUM_TRUNCATE_LOCK_WAIT_INTERVAL, LVRelState::verbose, WAIT_EVENT_VACUUM_TRUNCATE, WaitLatch(), WL_EXIT_ON_PM_DEATH, WL_LATCH_SET, and WL_TIMEOUT.

Referenced by heap_vacuum_rel().

lazy_vacuum()

static void lazy_vacuum ( LVRelState *  vacrel )

static

Definition at line 1860 of file vacuumlazy.c.

{
    bool        bypass;
 
    /* Should not end up here with no indexes */
    Assert(vacrel->nindexes > 0);
    Assert(vacrel->lpdead_item_pages > 0);
 
    if (!vacrel->do_index_vacuuming)
    {
        Assert(!vacrel->do_index_cleanup);
        vacrel->dead_items->num_items = 0;
        return;
    }
 
    /*
     * Consider bypassing index vacuuming (and heap vacuuming) entirely.
     *
     * We currently only do this in cases where the number of LP_DEAD items
     * for the entire VACUUM operation is close to zero.  This avoids sharp
     * discontinuities in the duration and overhead of successive VACUUM
     * operations that run against the same table with a fixed workload.
     * Ideally, successive VACUUM operations will behave as if there are
     * exactly zero LP_DEAD items in cases where there are close to zero.
     *
     * This is likely to be helpful with a table that is continually affected
     * by UPDATEs that can mostly apply the HOT optimization, but occasionally
     * have small aberrations that lead to just a few heap pages retaining
     * only one or two LP_DEAD items.  This is pretty common; even when the
     * DBA goes out of their way to make UPDATEs use HOT, it is practically
     * impossible to predict whether HOT will be applied in 100% of cases.
     * It's far easier to ensure that 99%+ of all UPDATEs against a table use
     * HOT through careful tuning.
     */
    bypass = false;
    if (vacrel->consider_bypass_optimization && vacrel->rel_pages > 0)
    {
        BlockNumber threshold;
 
        Assert(vacrel->num_index_scans == 0);
        Assert(vacrel->lpdead_items == vacrel->dead_items->num_items);
        Assert(vacrel->do_index_vacuuming);
        Assert(vacrel->do_index_cleanup);
 
        /*
         * This crossover point at which we'll start to do index vacuuming is
         * expressed as a percentage of the total number of heap pages in the
         * table that are known to have at least one LP_DEAD item.  This is
         * much more important than the total number of LP_DEAD items, since
         * it's a proxy for the number of heap pages whose visibility map bits
         * cannot be set on account of bypassing index and heap vacuuming.
         *
         * We apply one further precautionary test: the space currently used
         * to store the TIDs (TIDs that now all point to LP_DEAD items) must
         * not exceed 32MB.  This limits the risk that we will bypass index
         * vacuuming again and again until eventually there is a VACUUM whose
         * dead_items space is not CPU cache resident.
         *
         * We don't take any special steps to remember the LP_DEAD items (such
         * as counting them in new_dead_tuples report to the stats collector)
         * when the optimization is applied.  Though the accounting used in
         * analyze.c's acquire_sample_rows() will recognize the same LP_DEAD
         * items as dead rows in its own stats collector report, that's okay.
         * The discrepancy should be negligible.  If this optimization is ever
         * expanded to cover more cases then this may need to be reconsidered.
         */
        threshold = (double) vacrel->rel_pages * BYPASS_THRESHOLD_PAGES;
        bypass = (vacrel->lpdead_item_pages < threshold &&
                  vacrel->lpdead_items < MAXDEADITEMS(32L * 1024L * 1024L));
    }
 
    if (bypass)
    {
        /*
         * There are almost zero TIDs.  Behave as if there were precisely
         * zero: bypass index vacuuming, but do index cleanup.
         *
         * We expect that the ongoing VACUUM operation will finish very
         * quickly, so there is no point in considering speeding up as a
         * failsafe against wraparound failure. (Index cleanup is expected to
         * finish very quickly in cases where there were no ambulkdelete()
         * calls.)
         */
        vacrel->do_index_vacuuming = false;
    }
    else if (lazy_vacuum_all_indexes(vacrel))
    {
        /*
         * We successfully completed a round of index vacuuming.  Do related
         * heap vacuuming now.
         */
        lazy_vacuum_heap_rel(vacrel);
    }
    else
    {
        /*
         * Failsafe case.
         *
         * We attempted index vacuuming, but didn't finish a full round/full
         * index scan.  This happens when relfrozenxid or relminmxid is too
         * far in the past.
         *
         * From this point on the VACUUM operation will do no further index
         * vacuuming or heap vacuuming.  This VACUUM operation won't end up
         * back here again.
         */
        Assert(vacrel->failsafe_active);
    }
 
    /*
     * Forget the LP_DEAD items that we just vacuumed (or just decided to not
     * vacuum)
     */
    vacrel->dead_items->num_items = 0;
}

References Assert(), BYPASS_THRESHOLD_PAGES, LVRelState::consider_bypass_optimization, LVRelState::dead_items, LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, LVRelState::failsafe_active, lazy_vacuum_all_indexes(), lazy_vacuum_heap_rel(), LVRelState::lpdead_item_pages, LVRelState::lpdead_items, MAXDEADITEMS, LVRelState::nindexes, LVRelState::num_index_scans, VacDeadItems::num_items, and LVRelState::rel_pages.

Referenced by lazy_scan_heap().

lazy_vacuum_all_indexes()

static bool lazy_vacuum_all_indexes ( LVRelState *  vacrel )

static

Definition at line 1985 of file vacuumlazy.c.

{
    bool        allindexes = true;
 
    Assert(vacrel->nindexes > 0);
    Assert(vacrel->do_index_vacuuming);
    Assert(vacrel->do_index_cleanup);
    Assert(TransactionIdIsNormal(vacrel->relfrozenxid));
    Assert(MultiXactIdIsValid(vacrel->relminmxid));
 
    /* Precheck for XID wraparound emergencies */
    if (lazy_check_wraparound_failsafe(vacrel))
    {
        /* Wraparound emergency -- don't even start an index scan */
        return false;
    }
 
    /* Report that we are now vacuuming indexes */
    pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                 PROGRESS_VACUUM_PHASE_VACUUM_INDEX);
 
    if (!ParallelVacuumIsActive(vacrel))
    {
        for (int idx = 0; idx < vacrel->nindexes; idx++)
        {
            Relation    indrel = vacrel->indrels[idx];
            IndexBulkDeleteResult *istat = vacrel->indstats[idx];
 
            vacrel->indstats[idx] =
                lazy_vacuum_one_index(indrel, istat, vacrel->old_live_tuples,
                                      vacrel);
 
            if (lazy_check_wraparound_failsafe(vacrel))
            {
                /* Wraparound emergency -- end current index scan */
                allindexes = false;
                break;
            }
        }
    }
    else
    {
        /* Outsource everything to parallel variant */
        parallel_vacuum_bulkdel_all_indexes(vacrel->pvs, vacrel->old_live_tuples,
                                            vacrel->num_index_scans);
 
        /*
         * Do a postcheck to consider applying wraparound failsafe now.  Note
         * that parallel VACUUM only gets the precheck and this postcheck.
         */
        if (lazy_check_wraparound_failsafe(vacrel))
            allindexes = false;
    }
 
    /*
     * We delete all LP_DEAD items from the first heap pass in all indexes on
     * each call here (except calls where we choose to do the failsafe). This
     * makes the next call to lazy_vacuum_heap_rel() safe (except in the event
     * of the failsafe triggering, which prevents the next call from taking
     * place).
     */
    Assert(vacrel->num_index_scans > 0 ||
           vacrel->dead_items->num_items == vacrel->lpdead_items);
    Assert(allindexes || vacrel->failsafe_active);
 
    /*
     * Increase and report the number of index scans.
     *
     * We deliberately include the case where we started a round of bulk
     * deletes that we weren't able to finish due to the failsafe triggering.
     */
    vacrel->num_index_scans++;
    pgstat_progress_update_param(PROGRESS_VACUUM_NUM_INDEX_VACUUMS,
                                 vacrel->num_index_scans);
 
    return allindexes;
}

References Assert(), LVRelState::dead_items, LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, LVRelState::failsafe_active, idx(), LVRelState::indrels, LVRelState::indstats, lazy_check_wraparound_failsafe(), lazy_vacuum_one_index(), LVRelState::lpdead_items, MultiXactIdIsValid, LVRelState::nindexes, LVRelState::num_index_scans, VacDeadItems::num_items, LVRelState::old_live_tuples, parallel_vacuum_bulkdel_all_indexes(), ParallelVacuumIsActive, pgstat_progress_update_param(), PROGRESS_VACUUM_NUM_INDEX_VACUUMS, PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_VACUUM_INDEX, LVRelState::pvs, LVRelState::relfrozenxid, LVRelState::relminmxid, and TransactionIdIsNormal.

Referenced by lazy_vacuum().

lazy_vacuum_heap_page()

static int lazy_vacuum_heap_page ( LVRelState *  vacrel, BlockNumber  blkno, Buffer  buffer, int  index, Buffer *  vmbuffer  )

static

Definition at line 2175 of file vacuumlazy.c.

{
    VacDeadItems *dead_items = vacrel->dead_items;
    Page        page = BufferGetPage(buffer);
    OffsetNumber unused[MaxHeapTuplesPerPage];
    int         uncnt = 0;
    TransactionId visibility_cutoff_xid;
    bool        all_frozen;
    LVSavedErrInfo saved_err_info;
 
    Assert(vacrel->nindexes == 0 || vacrel->do_index_vacuuming);
 
    pgstat_progress_update_param(PROGRESS_VACUUM_HEAP_BLKS_VACUUMED, blkno);
 
    /* Update error traceback information */
    update_vacuum_error_info(vacrel, &saved_err_info,
                             VACUUM_ERRCB_PHASE_VACUUM_HEAP, blkno,
                             InvalidOffsetNumber);
 
    START_CRIT_SECTION();
 
    for (; index < dead_items->num_items; index++)
    {
        BlockNumber tblk;
        OffsetNumber toff;
        ItemId      itemid;
 
        tblk = ItemPointerGetBlockNumber(&dead_items->items[index]);
        if (tblk != blkno)
            break;              /* past end of tuples for this block */
        toff = ItemPointerGetOffsetNumber(&dead_items->items[index]);
        itemid = PageGetItemId(page, toff);
 
        Assert(ItemIdIsDead(itemid) && !ItemIdHasStorage(itemid));
        ItemIdSetUnused(itemid);
        unused[uncnt++] = toff;
    }
 
    Assert(uncnt > 0);
 
    /* Attempt to truncate line pointer array now */
    PageTruncateLinePointerArray(page);
 
    /*
     * Mark buffer dirty before we write WAL.
     */
    MarkBufferDirty(buffer);
 
    /* XLOG stuff */
    if (RelationNeedsWAL(vacrel->rel))
    {
        xl_heap_vacuum xlrec;
        XLogRecPtr  recptr;
 
        xlrec.nunused = uncnt;
 
        XLogBeginInsert();
        XLogRegisterData((char *) &xlrec, SizeOfHeapVacuum);
 
        XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
        XLogRegisterBufData(0, (char *) unused, uncnt * sizeof(OffsetNumber));
 
        recptr = XLogInsert(RM_HEAP2_ID, XLOG_HEAP2_VACUUM);
 
        PageSetLSN(page, recptr);
    }
 
    /*
     * End critical section, so we safely can do visibility tests (which
     * possibly need to perform IO and allocate memory!). If we crash now the
     * page (including the corresponding vm bit) might not be marked all
     * visible, but that's fine. A later vacuum will fix that.
     */
    END_CRIT_SECTION();
 
    /*
     * Now that we have removed the LD_DEAD items from the page, once again
     * check if the page has become all-visible.  The page is already marked
     * dirty, exclusively locked, and, if needed, a full page image has been
     * emitted.
     */
    if (heap_page_is_all_visible(vacrel, buffer, &visibility_cutoff_xid,
                                 &all_frozen))
        PageSetAllVisible(page);
 
    /*
     * All the changes to the heap page have been done. If the all-visible
     * flag is now set, also set the VM all-visible bit (and, if possible, the
     * all-frozen bit) unless this has already been done previously.
     */
    if (PageIsAllVisible(page))
    {
        uint8       flags = 0;
        uint8       vm_status = visibilitymap_get_status(vacrel->rel,
                                                         blkno, vmbuffer);
 
        /* Set the VM all-frozen bit to flag, if needed */
        if ((vm_status & VISIBILITYMAP_ALL_VISIBLE) == 0)
            flags |= VISIBILITYMAP_ALL_VISIBLE;
        if ((vm_status & VISIBILITYMAP_ALL_FROZEN) == 0 && all_frozen)
            flags |= VISIBILITYMAP_ALL_FROZEN;
 
        Assert(BufferIsValid(*vmbuffer));
        if (flags != 0)
            visibilitymap_set(vacrel->rel, blkno, buffer, InvalidXLogRecPtr,
                              *vmbuffer, visibility_cutoff_xid, flags);
    }
 
    /* Revert to the previous phase information for error traceback */
    restore_vacuum_error_info(vacrel, &saved_err_info);
    return index;
}

References Assert(), BufferGetPage, BufferIsValid, LVRelState::dead_items, LVRelState::do_index_vacuuming, END_CRIT_SECTION, heap_page_is_all_visible(), InvalidOffsetNumber, InvalidXLogRecPtr, ItemIdHasStorage, ItemIdIsDead, ItemIdSetUnused, ItemPointerGetBlockNumber, ItemPointerGetOffsetNumber, VacDeadItems::items, MarkBufferDirty(), MaxHeapTuplesPerPage, LVRelState::nindexes, VacDeadItems::num_items, xl_heap_vacuum::nunused, PageGetItemId, PageIsAllVisible, PageSetAllVisible, PageSetLSN, PageTruncateLinePointerArray(), pgstat_progress_update_param(), PROGRESS_VACUUM_HEAP_BLKS_VACUUMED, REGBUF_STANDARD, LVRelState::rel, RelationNeedsWAL, restore_vacuum_error_info(), SizeOfHeapVacuum, START_CRIT_SECTION, update_vacuum_error_info(), VACUUM_ERRCB_PHASE_VACUUM_HEAP, VISIBILITYMAP_ALL_FROZEN, VISIBILITYMAP_ALL_VISIBLE, visibilitymap_get_status(), visibilitymap_set(), XLOG_HEAP2_VACUUM, XLogBeginInsert(), XLogInsert(), XLogRegisterBufData(), XLogRegisterBuffer(), and XLogRegisterData().

Referenced by lazy_scan_heap(), and lazy_vacuum_heap_rel().

lazy_vacuum_heap_rel()

static void lazy_vacuum_heap_rel ( LVRelState *  vacrel )

static

Definition at line 2082 of file vacuumlazy.c.

{
    int         index;
    BlockNumber vacuumed_pages;
    Buffer      vmbuffer = InvalidBuffer;
    LVSavedErrInfo saved_err_info;
 
    Assert(vacrel->do_index_vacuuming);
    Assert(vacrel->do_index_cleanup);
    Assert(vacrel->num_index_scans > 0);
 
    /* Report that we are now vacuuming the heap */
    pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
                                 PROGRESS_VACUUM_PHASE_VACUUM_HEAP);
 
    /* Update error traceback information */
    update_vacuum_error_info(vacrel, &saved_err_info,
                             VACUUM_ERRCB_PHASE_VACUUM_HEAP,
                             InvalidBlockNumber, InvalidOffsetNumber);
 
    vacuumed_pages = 0;
 
    index = 0;
    while (index < vacrel->dead_items->num_items)
    {
        BlockNumber tblk;
        Buffer      buf;
        Page        page;
        Size        freespace;
 
        vacuum_delay_point();
 
        tblk = ItemPointerGetBlockNumber(&vacrel->dead_items->items[index]);
        vacrel->blkno = tblk;
        buf = ReadBufferExtended(vacrel->rel, MAIN_FORKNUM, tblk, RBM_NORMAL,
                                 vacrel->bstrategy);
        LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
        index = lazy_vacuum_heap_page(vacrel, tblk, buf, index, &vmbuffer);
 
        /* Now that we've vacuumed the page, record its available space */
        page = BufferGetPage(buf);
        freespace = PageGetHeapFreeSpace(page);
 
        UnlockReleaseBuffer(buf);
        RecordPageWithFreeSpace(vacrel->rel, tblk, freespace);
        vacuumed_pages++;
    }
 
    /* Clear the block number information */
    vacrel->blkno = InvalidBlockNumber;
 
    if (BufferIsValid(vmbuffer))
    {
        ReleaseBuffer(vmbuffer);
        vmbuffer = InvalidBuffer;
    }
 
    /*
     * We set all LP_DEAD items from the first heap pass to LP_UNUSED during
     * the second heap pass.  No more, no less.
     */
    Assert(index > 0);
    Assert(vacrel->num_index_scans > 1 ||
           (index == vacrel->lpdead_items &&
            vacuumed_pages == vacrel->lpdead_item_pages));
 
    ereport(DEBUG2,
            (errmsg("table \"%s\": removed %lld dead item identifiers in %u pages",
                    vacrel->relname, (long long) index, vacuumed_pages)));
 
    /* Revert to the previous phase information for error traceback */
    restore_vacuum_error_info(vacrel, &saved_err_info);
}

References Assert(), LVRelState::blkno, LVRelState::bstrategy, buf, BUFFER_LOCK_EXCLUSIVE, BufferGetPage, BufferIsValid, LVRelState::dead_items, DEBUG2, LVRelState::do_index_cleanup, LVRelState::do_index_vacuuming, ereport, errmsg(), InvalidBlockNumber, InvalidBuffer, InvalidOffsetNumber, ItemPointerGetBlockNumber, VacDeadItems::items, lazy_vacuum_heap_page(), LockBuffer(), LVRelState::lpdead_item_pages, LVRelState::lpdead_items, MAIN_FORKNUM, LVRelState::num_index_scans, PageGetHeapFreeSpace(), pgstat_progress_update_param(), PROGRESS_VACUUM_PHASE, PROGRESS_VACUUM_PHASE_VACUUM_HEAP, RBM_NORMAL, ReadBufferExtended(), RecordPageWithFreeSpace(), LVRelState::rel, ReleaseBuffer(), LVRelState::relname, restore_vacuum_error_info(), UnlockReleaseBuffer(), update_vacuum_error_info(), vacuum_delay_point(), and VACUUM_ERRCB_PHASE_VACUUM_HEAP.

Referenced by lazy_vacuum().

lazy_vacuum_one_index()

static IndexBulkDeleteResult * lazy_vacuum_one_index ( Relation  indrel, IndexBulkDeleteResult *  istat, double  reltuples, LVRelState *  vacrel  )

static

Definition at line 2450 of file vacuumlazy.c.

{
    IndexVacuumInfo ivinfo;
    LVSavedErrInfo saved_err_info;
 
    ivinfo.index = indrel;
    ivinfo.analyze_only = false;
    ivinfo.report_progress = false;
    ivinfo.estimated_count = true;
    ivinfo.message_level = DEBUG2;
    ivinfo.num_heap_tuples = reltuples;
    ivinfo.strategy = vacrel->bstrategy;
 
    /*
     * Update error traceback information.
     *
     * The index name is saved during this phase and restored immediately
     * after this phase.  See vacuum_error_callback.
     */
    Assert(vacrel->indname == NULL);
    vacrel->indname = pstrdup(RelationGetRelationName(indrel));
    update_vacuum_error_info(vacrel, &saved_err_info,
                             VACUUM_ERRCB_PHASE_VACUUM_INDEX,
                             InvalidBlockNumber, InvalidOffsetNumber);
 
    /* Do bulk deletion */
    istat = vac_bulkdel_one_index(&ivinfo, istat, (void *) vacrel->dead_items);
 
    /* Revert to the previous phase information for error traceback */
    restore_vacuum_error_info(vacrel, &saved_err_info);
    pfree(vacrel->indname);
    vacrel->indname = NULL;
 
    return istat;
}

References IndexVacuumInfo::analyze_only, Assert(), LVRelState::bstrategy, LVRelState::dead_items, DEBUG2, IndexVacuumInfo::estimated_count, IndexVacuumInfo::index, LVRelState::indname, InvalidBlockNumber, InvalidOffsetNumber, IndexVacuumInfo::message_level, IndexVacuumInfo::num_heap_tuples, pfree(), pstrdup(), RelationGetRelationName, IndexVacuumInfo::report_progress, restore_vacuum_error_info(), IndexVacuumInfo::strategy, update_vacuum_error_info(), vac_bulkdel_one_index(), and VACUUM_ERRCB_PHASE_VACUUM_INDEX.

Referenced by lazy_vacuum_all_indexes().

restore_vacuum_error_info()

static void restore_vacuum_error_info ( LVRelState *  vacrel, const LVSavedErrInfo *  saved_vacrel  )

static

Definition at line 3200 of file vacuumlazy.c.

{
    vacrel->blkno = saved_vacrel->blkno;
    vacrel->offnum = saved_vacrel->offnum;
    vacrel->phase = saved_vacrel->phase;
}

References LVRelState::blkno, LVSavedErrInfo::blkno, LVRelState::offnum, LVSavedErrInfo::offnum, LVRelState::phase, and LVSavedErrInfo::phase.

Referenced by lazy_cleanup_one_index(), lazy_vacuum_heap_page(), lazy_vacuum_heap_rel(), and lazy_vacuum_one_index().

should_attempt_truncation()

static bool should_attempt_truncation ( LVRelState *  vacrel )

static

Definition at line 2557 of file vacuumlazy.c.

{
    BlockNumber possibly_freeable;
 
    if (!vacrel->do_rel_truncate || vacrel->failsafe_active)
        return false;
 
    possibly_freeable = vacrel->rel_pages - vacrel->nonempty_pages;
    if (possibly_freeable > 0 &&
        (possibly_freeable >= REL_TRUNCATE_MINIMUM ||
         possibly_freeable >= vacrel->rel_pages / REL_TRUNCATE_FRACTION) &&
        old_snapshot_threshold < 0)
        return true;
    else
        return false;
}

References LVRelState::do_rel_truncate, LVRelState::failsafe_active, LVRelState::nonempty_pages, old_snapshot_threshold, LVRelState::rel_pages, REL_TRUNCATE_FRACTION, and REL_TRUNCATE_MINIMUM.

Referenced by heap_vacuum_rel().

update_index_statistics()

static void update_index_statistics ( LVRelState *  vacrel )

static

Definition at line 3082 of file vacuumlazy.c.

{
    Relation   *indrels = vacrel->indrels;
    int         nindexes = vacrel->nindexes;
    IndexBulkDeleteResult **indstats = vacrel->indstats;
 
    Assert(!IsInParallelMode());
 
    for (int idx = 0; idx < nindexes; idx++)
    {
        Relation    indrel = indrels[idx];
        IndexBulkDeleteResult *istat = indstats[idx];
 
        if (istat == NULL || istat->estimated_count)
            continue;
 
        /* Update index statistics */
        vac_update_relstats(indrel,
                            istat->num_pages,
                            istat->num_index_tuples,
                            0,
                            false,
                            InvalidTransactionId,
                            InvalidMultiXactId,
                            false);
    }
}

References Assert(), IndexBulkDeleteResult::estimated_count, idx(), LVRelState::indrels, LVRelState::indstats, InvalidMultiXactId, InvalidTransactionId, IsInParallelMode(), LVRelState::nindexes, IndexBulkDeleteResult::num_index_tuples, IndexBulkDeleteResult::num_pages, and vac_update_relstats().

Referenced by lazy_scan_heap().

update_vacuum_error_info()

static void update_vacuum_error_info ( LVRelState *  vacrel, LVSavedErrInfo *  saved_vacrel, int  phase, BlockNumber  blkno, OffsetNumber  offnum  )

static

Definition at line 3181 of file vacuumlazy.c.

{
    if (saved_vacrel)
    {
        saved_vacrel->offnum = vacrel->offnum;
        saved_vacrel->blkno = vacrel->blkno;
        saved_vacrel->phase = vacrel->phase;
    }
 
    vacrel->blkno = blkno;
    vacrel->offnum = offnum;
    vacrel->phase = phase;
}

References LVRelState::blkno, LVSavedErrInfo::blkno, LVRelState::offnum, LVSavedErrInfo::offnum, LVRelState::phase, and LVSavedErrInfo::phase.

Referenced by heap_vacuum_rel(), lazy_cleanup_one_index(), lazy_scan_heap(), lazy_vacuum_heap_page(), lazy_vacuum_heap_rel(), and lazy_vacuum_one_index().

vacuum_error_callback()

static void vacuum_error_callback ( void *  arg )

static

Definition at line 3117 of file vacuumlazy.c.

{
    LVRelState *errinfo = arg;
 
    switch (errinfo->phase)
    {
        case VACUUM_ERRCB_PHASE_SCAN_HEAP:
            if (BlockNumberIsValid(errinfo->blkno))
            {
                if (OffsetNumberIsValid(errinfo->offnum))
                    errcontext("while scanning block %u offset %u of relation \"%s.%s\"",
                               errinfo->blkno, errinfo->offnum, errinfo->relnamespace, errinfo->relname);
                else
                    errcontext("while scanning block %u of relation \"%s.%s\"",
                               errinfo->blkno, errinfo->relnamespace, errinfo->relname);
            }
            else
                errcontext("while scanning relation \"%s.%s\"",
                           errinfo->relnamespace, errinfo->relname);
            break;
 
        case VACUUM_ERRCB_PHASE_VACUUM_HEAP:
            if (BlockNumberIsValid(errinfo->blkno))
            {
                if (OffsetNumberIsValid(errinfo->offnum))
                    errcontext("while vacuuming block %u offset %u of relation \"%s.%s\"",
                               errinfo->blkno, errinfo->offnum, errinfo->relnamespace, errinfo->relname);
                else
                    errcontext("while vacuuming block %u of relation \"%s.%s\"",
                               errinfo->blkno, errinfo->relnamespace, errinfo->relname);
            }
            else
                errcontext("while vacuuming relation \"%s.%s\"",
                           errinfo->relnamespace, errinfo->relname);
            break;
 
        case VACUUM_ERRCB_PHASE_VACUUM_INDEX:
            errcontext("while vacuuming index \"%s\" of relation \"%s.%s\"",
                       errinfo->indname, errinfo->relnamespace, errinfo->relname);
            break;
 
        case VACUUM_ERRCB_PHASE_INDEX_CLEANUP:
            errcontext("while cleaning up index \"%s\" of relation \"%s.%s\"",
                       errinfo->indname, errinfo->relnamespace, errinfo->relname);
            break;
 
        case VACUUM_ERRCB_PHASE_TRUNCATE:
            if (BlockNumberIsValid(errinfo->blkno))
                errcontext("while truncating relation \"%s.%s\" to %u blocks",
                           errinfo->relnamespace, errinfo->relname, errinfo->blkno);
            break;
 
        case VACUUM_ERRCB_PHASE_UNKNOWN:
        default:
            return;             /* do nothing; the errinfo may not be
                                 * initialized */
    }
}

References arg, LVRelState::blkno, BlockNumberIsValid, errcontext, LVRelState::indname, LVRelState::offnum, OffsetNumberIsValid, LVRelState::phase, LVRelState::relname, LVRelState::relnamespace, VACUUM_ERRCB_PHASE_INDEX_CLEANUP, VACUUM_ERRCB_PHASE_SCAN_HEAP, VACUUM_ERRCB_PHASE_TRUNCATE, VACUUM_ERRCB_PHASE_UNKNOWN, VACUUM_ERRCB_PHASE_VACUUM_HEAP, and VACUUM_ERRCB_PHASE_VACUUM_INDEX.

Referenced by heap_vacuum_rel().