pgstatindex.c File Reference

#include "postgres.h"
#include "access/gin_private.h"
#include "access/hash.h"
#include "access/htup_details.h"
#include "access/nbtree.h"
#include "access/relation.h"
#include "catalog/namespace.h"
#include "catalog/pg_am.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
#include "storage/read_stream.h"
#include "utils/rel.h"
#include "utils/varlena.h"

Include dependency graph for pgstatindex.c:

Go to the source code of this file.

Data Structures
struct	BTIndexStat
struct	GinIndexStat
struct	HashIndexStat

Macros
#define	IS_INDEX(r)   ((r)->rd_rel->relkind == RELKIND_INDEX)
#define	IS_BTREE(r)   ((r)->rd_rel->relam == BTREE_AM_OID)
#define	IS_GIN(r)   ((r)->rd_rel->relam == GIN_AM_OID)
#define	IS_HASH(r)   ((r)->rd_rel->relam == HASH_AM_OID)

Typedefs
typedef struct BTIndexStat	BTIndexStat
typedef struct GinIndexStat	GinIndexStat
typedef struct HashIndexStat	HashIndexStat

Functions
	PG_FUNCTION_INFO_V1 (pgstatindex)
	PG_FUNCTION_INFO_V1 (pgstatindexbyid)
	PG_FUNCTION_INFO_V1 (pg_relpages)
	PG_FUNCTION_INFO_V1 (pg_relpagesbyid)
	PG_FUNCTION_INFO_V1 (pgstatginindex)
	PG_FUNCTION_INFO_V1 (pgstathashindex)
	PG_FUNCTION_INFO_V1 (pgstatindex_v1_5)
	PG_FUNCTION_INFO_V1 (pgstatindexbyid_v1_5)
	PG_FUNCTION_INFO_V1 (pg_relpages_v1_5)
	PG_FUNCTION_INFO_V1 (pg_relpagesbyid_v1_5)
	PG_FUNCTION_INFO_V1 (pgstatginindex_v1_5)
Datum	pgstatginindex_internal (Oid relid, FunctionCallInfo fcinfo)
static Datum	pgstatindex_impl (Relation rel, FunctionCallInfo fcinfo)
static int64	pg_relpages_impl (Relation rel)
static void	GetHashPageStats (Page page, HashIndexStat *stats)
Datum	pgstatindex (PG_FUNCTION_ARGS)
Datum	pgstatindex_v1_5 (PG_FUNCTION_ARGS)
Datum	pgstatindexbyid (PG_FUNCTION_ARGS)
Datum	pgstatindexbyid_v1_5 (PG_FUNCTION_ARGS)
Datum	pg_relpages (PG_FUNCTION_ARGS)
Datum	pg_relpages_v1_5 (PG_FUNCTION_ARGS)
Datum	pg_relpagesbyid (PG_FUNCTION_ARGS)
Datum	pg_relpagesbyid_v1_5 (PG_FUNCTION_ARGS)
Datum	pgstatginindex (PG_FUNCTION_ARGS)
Datum	pgstatginindex_v1_5 (PG_FUNCTION_ARGS)
Datum	pgstathashindex (PG_FUNCTION_ARGS)

Macro Definition Documentation

IS_BTREE

#define IS_BTREE

(

r

)

((r)->rd_rel->relam == BTREE_AM_OID)

Definition at line 69 of file pgstatindex.c.

IS_GIN

#define IS_GIN

(

r

)

((r)->rd_rel->relam == GIN_AM_OID)

Definition at line 70 of file pgstatindex.c.

IS_HASH

#define IS_HASH

(

r

)

((r)->rd_rel->relam == HASH_AM_OID)

Definition at line 71 of file pgstatindex.c.

IS_INDEX

#define IS_INDEX

(

r

)

((r)->rd_rel->relkind == RELKIND_INDEX)

Definition at line 68 of file pgstatindex.c.

Typedef Documentation

BTIndexStat

typedef struct BTIndexStat BTIndexStat

GinIndexStat

typedef struct GinIndexStat GinIndexStat

HashIndexStat

typedef struct HashIndexStat HashIndexStat

Function Documentation

GetHashPageStats()

static void GetHashPageStats ( Page  page, HashIndexStat *  stats  )

static

Definition at line 794 of file pgstatindex.c.

{
    OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
    int         off;
 
    /* count live and dead tuples, and free space */
    for (off = FirstOffsetNumber; off <= maxoff; off++)
    {
        ItemId      id = PageGetItemId(page, off);
 
        if (!ItemIdIsDead(id))
            stats->live_items++;
        else
            stats->dead_items++;
    }
    stats->free_space += PageGetExactFreeSpace(page);
}

References HashIndexStat::dead_items, FirstOffsetNumber, HashIndexStat::free_space, ItemIdIsDead, HashIndexStat::live_items, PageGetExactFreeSpace(), PageGetItemId(), and PageGetMaxOffsetNumber().

Referenced by pgstathashindex().

PG_FUNCTION_INFO_V1() [1/11]

PG_FUNCTION_INFO_V1

(

pg_relpages

)

PG_FUNCTION_INFO_V1() [2/11]

PG_FUNCTION_INFO_V1

(

pg_relpages_v1_5

)

PG_FUNCTION_INFO_V1() [3/11]

PG_FUNCTION_INFO_V1

(

pg_relpagesbyid

)

PG_FUNCTION_INFO_V1() [4/11]

PG_FUNCTION_INFO_V1

(

pg_relpagesbyid_v1_5

)

PG_FUNCTION_INFO_V1() [5/11]

PG_FUNCTION_INFO_V1

(

pgstatginindex

)

PG_FUNCTION_INFO_V1() [6/11]

PG_FUNCTION_INFO_V1

(

pgstatginindex_v1_5

)

PG_FUNCTION_INFO_V1() [7/11]

PG_FUNCTION_INFO_V1

(

pgstathashindex

)

PG_FUNCTION_INFO_V1() [8/11]

PG_FUNCTION_INFO_V1

(

pgstatindex

)

PG_FUNCTION_INFO_V1() [9/11]

PG_FUNCTION_INFO_V1

(

pgstatindex_v1_5

)

PG_FUNCTION_INFO_V1() [10/11]

PG_FUNCTION_INFO_V1

(

pgstatindexbyid

)

PG_FUNCTION_INFO_V1() [11/11]

PG_FUNCTION_INFO_V1

(

pgstatindexbyid_v1_5

)

pg_relpages()

Datum pg_relpages

(

PG_FUNCTION_ARGS

)

Definition at line 413 of file pgstatindex.c.

{
    text       *relname = PG_GETARG_TEXT_PP(0);
    Relation    rel;
    RangeVar   *relrv;
 
    if (!superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to use pgstattuple functions")));
 
    relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
    rel = relation_openrv(relrv, AccessShareLock);
 
    PG_RETURN_INT64(pg_relpages_impl(rel));
}

References AccessShareLock, ereport, errcode(), errmsg, ERROR, fb(), makeRangeVarFromNameList(), PG_GETARG_TEXT_PP, pg_relpages_impl(), PG_RETURN_INT64, relation_openrv(), relname, superuser(), and textToQualifiedNameList().

pg_relpages_impl()

static int64 pg_relpages_impl ( Relation  rel )

static

Definition at line 474 of file pgstatindex.c.

{
    int64       relpages;
 
    if (!RELKIND_HAS_STORAGE(rel->rd_rel->relkind))
        ereport(ERROR,
                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                 errmsg("cannot get page count of relation \"%s\"",
                        RelationGetRelationName(rel)),
                 errdetail_relkind_not_supported(rel->rd_rel->relkind)));
 
    /* note: this will work OK on non-local temp tables */
 
    relpages = RelationGetNumberOfBlocks(rel);
 
    relation_close(rel, AccessShareLock);
 
    return relpages;
}

References AccessShareLock, ereport, errcode(), errdetail_relkind_not_supported(), errmsg, ERROR, fb(), RelationData::rd_rel, relation_close(), RelationGetNumberOfBlocks, and RelationGetRelationName.

Referenced by pg_relpages(), pg_relpages_v1_5(), pg_relpagesbyid(), and pg_relpagesbyid_v1_5().

pg_relpages_v1_5()

Datum pg_relpages_v1_5

(

PG_FUNCTION_ARGS

)

Definition at line 432 of file pgstatindex.c.

{
    text       *relname = PG_GETARG_TEXT_PP(0);
    Relation    rel;
    RangeVar   *relrv;
 
    relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
    rel = relation_openrv(relrv, AccessShareLock);
 
    PG_RETURN_INT64(pg_relpages_impl(rel));
}

References AccessShareLock, fb(), makeRangeVarFromNameList(), PG_GETARG_TEXT_PP, pg_relpages_impl(), PG_RETURN_INT64, relation_openrv(), relname, and textToQualifiedNameList().

pg_relpagesbyid()

Datum pg_relpagesbyid

(

PG_FUNCTION_ARGS

)

Definition at line 446 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
    Relation    rel;
 
    if (!superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to use pgstattuple functions")));
 
    rel = relation_open(relid, AccessShareLock);
 
    PG_RETURN_INT64(pg_relpages_impl(rel));
}

References AccessShareLock, ereport, errcode(), errmsg, ERROR, fb(), PG_GETARG_OID, pg_relpages_impl(), PG_RETURN_INT64, relation_open(), and superuser().

pg_relpagesbyid_v1_5()

Datum pg_relpagesbyid_v1_5

(

PG_FUNCTION_ARGS

)

Definition at line 463 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
    Relation    rel;
 
    rel = relation_open(relid, AccessShareLock);
 
    PG_RETURN_INT64(pg_relpages_impl(rel));
}

References AccessShareLock, PG_GETARG_OID, pg_relpages_impl(), PG_RETURN_INT64, and relation_open().

pgstatginindex()

Datum pgstatginindex

(

PG_FUNCTION_ARGS

)

Definition at line 503 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
 
    if (!superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to use pgstattuple functions")));
 
    PG_RETURN_DATUM(pgstatginindex_internal(relid, fcinfo));
}

References ereport, errcode(), errmsg, ERROR, fb(), PG_GETARG_OID, PG_RETURN_DATUM, pgstatginindex_internal(), and superuser().

pgstatginindex_internal()

Datum pgstatginindex_internal	(	Oid	relid,
		FunctionCallInfo	fcinfo
	)

Definition at line 525 of file pgstatindex.c.

{
    Relation    rel;
    Buffer      buffer;
    Page        page;
    GinMetaPageData *metadata;
    GinIndexStat stats;
    HeapTuple   tuple;
    TupleDesc   tupleDesc;
    Datum       values[3];
    bool        nulls[3] = {false, false, false};
    Datum       result;
 
    /*
     * This uses relation_open() and not index_open().  The latter allows
     * partitioned indexes, and these are forbidden here.
     */
    rel = relation_open(relid, AccessShareLock);
 
    if (!IS_INDEX(rel) || !IS_GIN(rel))
        ereport(ERROR,
                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                 errmsg("relation \"%s\" is not a GIN index",
                        RelationGetRelationName(rel))));
 
    /*
     * Reject attempts to read non-local temporary relations; we would be
     * likely to get wrong data since we have no visibility into the owning
     * session's local buffers.
     */
    if (RELATION_IS_OTHER_TEMP(rel))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("cannot access temporary indexes of other sessions")));
 
    /* see pgstatindex_impl */
    if (!rel->rd_index->indisvalid)
        ereport(ERROR,
                (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                 errmsg("index \"%s\" is not valid",
                        RelationGetRelationName(rel))));
 
    /*
     * Read metapage
     */
    buffer = ReadBuffer(rel, GIN_METAPAGE_BLKNO);
    LockBuffer(buffer, GIN_SHARE);
    page = BufferGetPage(buffer);
    metadata = GinPageGetMeta(page);
 
    stats.version = metadata->ginVersion;
    stats.pending_pages = metadata->nPendingPages;
    stats.pending_tuples = metadata->nPendingHeapTuples;
 
    UnlockReleaseBuffer(buffer);
    relation_close(rel, AccessShareLock);
 
    /*
     * Build a tuple descriptor for our result type
     */
    if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
        elog(ERROR, "return type must be a row type");
 
    values[0] = Int32GetDatum(stats.version);
    values[1] = UInt32GetDatum(stats.pending_pages);
    values[2] = Int64GetDatum(stats.pending_tuples);
 
    /*
     * Build and return the tuple
     */
    tuple = heap_form_tuple(tupleDesc, values, nulls);
    result = HeapTupleGetDatum(tuple);
 
    return result;
}

References AccessShareLock, BufferGetPage(), elog, ereport, errcode(), errmsg, ERROR, fb(), get_call_result_type(), GIN_METAPAGE_BLKNO, GIN_SHARE, GinPageGetMeta, GinMetaPageData::ginVersion, heap_form_tuple(), HeapTupleGetDatum(), Int32GetDatum(), Int64GetDatum(), IS_GIN, IS_INDEX, LockBuffer(), GinMetaPageData::nPendingHeapTuples, GinMetaPageData::nPendingPages, GinIndexStat::pending_pages, GinIndexStat::pending_tuples, RelationData::rd_index, ReadBuffer(), relation_close(), RELATION_IS_OTHER_TEMP, relation_open(), RelationGetRelationName, TYPEFUNC_COMPOSITE, UInt32GetDatum(), UnlockReleaseBuffer(), values, and GinIndexStat::version.

Referenced by pgstatginindex(), and pgstatginindex_v1_5().

pgstatginindex_v1_5()

Datum pgstatginindex_v1_5

(

PG_FUNCTION_ARGS

)

Definition at line 517 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
 
    PG_RETURN_DATUM(pgstatginindex_internal(relid, fcinfo));
}

References PG_GETARG_OID, PG_RETURN_DATUM, and pgstatginindex_internal().

pgstathashindex()

Datum pgstathashindex

(

PG_FUNCTION_ARGS

)

Definition at line 608 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
    BlockNumber nblocks;
    BlockNumber blkno;
    Relation    rel;
    HashIndexStat stats;
    BufferAccessStrategy bstrategy;
    HeapTuple   tuple;
    TupleDesc   tupleDesc;
    Datum       values[8];
    bool        nulls[8] = {0};
    Buffer      metabuf;
    HashMetaPage metap;
    float8      free_percent;
    uint64      total_space;
    BlockRangeReadStreamPrivate p;
    ReadStream *stream;
    BlockNumber startblk;
 
    /*
     * This uses relation_open() and not index_open().  The latter allows
     * partitioned indexes, and these are forbidden here.
     */
    rel = relation_open(relid, AccessShareLock);
 
    if (!IS_INDEX(rel) || !IS_HASH(rel))
        ereport(ERROR,
                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                 errmsg("relation \"%s\" is not a hash index",
                        RelationGetRelationName(rel))));
 
    /*
     * Reject attempts to read non-local temporary relations; we would be
     * likely to get wrong data since we have no visibility into the owning
     * session's local buffers.
     */
    if (RELATION_IS_OTHER_TEMP(rel))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("cannot access temporary indexes of other sessions")));
 
    /* see pgstatindex_impl */
    if (!rel->rd_index->indisvalid)
        ereport(ERROR,
                (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                 errmsg("index \"%s\" is not valid",
                        RelationGetRelationName(rel))));
 
    /* Get the information we need from the metapage. */
    memset(&stats, 0, sizeof(stats));
    metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_READ, LH_META_PAGE);
    metap = HashPageGetMeta(BufferGetPage(metabuf));
    stats.version = metap->hashm_version;
    stats.space_per_page = metap->hashm_bsize;
    _hash_relbuf(rel, metabuf);
 
    /* Get the current relation length */
    nblocks = RelationGetNumberOfBlocks(rel);
 
    /* prepare access strategy for this index */
    bstrategy = GetAccessStrategy(BAS_BULKREAD);
 
    /* Scan all blocks except the metapage (0th page) using streaming reads */
    startblk = HASH_METAPAGE + 1;
 
    p.current_blocknum = startblk;
    p.last_exclusive = nblocks;
 
    /*
     * It is safe to use batchmode as block_range_read_stream_cb takes no
     * locks.
     */
    stream = read_stream_begin_relation(READ_STREAM_FULL |
                                        READ_STREAM_USE_BATCHING,
                                        bstrategy,
                                        rel,
                                        MAIN_FORKNUM,
                                        block_range_read_stream_cb,
                                        &p,
                                        0);
 
    for (blkno = startblk; blkno < nblocks; blkno++)
    {
        Buffer      buf;
        Page        page;
 
        CHECK_FOR_INTERRUPTS();
 
        buf = read_stream_next_buffer(stream, NULL);
        LockBuffer(buf, BUFFER_LOCK_SHARE);
        page = BufferGetPage(buf);
 
        if (PageIsNew(page))
            stats.unused_pages++;
        else if (PageGetSpecialSize(page) !=
                 MAXALIGN(sizeof(HashPageOpaqueData)))
            ereport(ERROR,
                    (errcode(ERRCODE_INDEX_CORRUPTED),
                     errmsg("index \"%s\" contains corrupted page at block %u",
                            RelationGetRelationName(rel),
                            BufferGetBlockNumber(buf))));
        else
        {
            HashPageOpaque opaque;
            int         pagetype;
 
            opaque = HashPageGetOpaque(page);
            pagetype = opaque->hasho_flag & LH_PAGE_TYPE;
 
            if (pagetype == LH_BUCKET_PAGE)
            {
                stats.bucket_pages++;
                GetHashPageStats(page, &stats);
            }
            else if (pagetype == LH_OVERFLOW_PAGE)
            {
                stats.overflow_pages++;
                GetHashPageStats(page, &stats);
            }
            else if (pagetype == LH_BITMAP_PAGE)
                stats.bitmap_pages++;
            else if (pagetype == LH_UNUSED_PAGE)
                stats.unused_pages++;
            else
                ereport(ERROR,
                        (errcode(ERRCODE_INDEX_CORRUPTED),
                         errmsg("unexpected page type 0x%04X in HASH index \"%s\" block %u",
                                opaque->hasho_flag, RelationGetRelationName(rel),
                                BufferGetBlockNumber(buf))));
        }
        UnlockReleaseBuffer(buf);
    }
 
    Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
    read_stream_end(stream);
 
    /* Done accessing the index */
    relation_close(rel, AccessShareLock);
 
    /* Count unused pages as free space. */
    stats.free_space += (uint64) stats.unused_pages * stats.space_per_page;
 
    /*
     * Total space available for tuples excludes the metapage and the bitmap
     * pages.
     */
    total_space = (uint64) (nblocks - (stats.bitmap_pages + 1)) *
        stats.space_per_page;
 
    if (total_space == 0)
        free_percent = 0.0;
    else
        free_percent = 100.0 * stats.free_space / total_space;
 
    /*
     * Build a tuple descriptor for our result type
     */
    if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
        elog(ERROR, "return type must be a row type");
 
    tupleDesc = BlessTupleDesc(tupleDesc);
 
    /*
     * Build and return the tuple
     */
    values[0] = Int32GetDatum(stats.version);
    values[1] = Int64GetDatum((int64) stats.bucket_pages);
    values[2] = Int64GetDatum((int64) stats.overflow_pages);
    values[3] = Int64GetDatum((int64) stats.bitmap_pages);
    values[4] = Int64GetDatum((int64) stats.unused_pages);
    values[5] = Int64GetDatum(stats.live_items);
    values[6] = Int64GetDatum(stats.dead_items);
    values[7] = Float8GetDatum(free_percent);
    tuple = heap_form_tuple(tupleDesc, values, nulls);
 
    PG_RETURN_DATUM(HeapTupleGetDatum(tuple));
}

References _hash_getbuf(), _hash_relbuf(), AccessShareLock, Assert, BAS_BULKREAD, HashIndexStat::bitmap_pages, BlessTupleDesc(), block_range_read_stream_cb(), HashIndexStat::bucket_pages, buf, BUFFER_LOCK_SHARE, BufferGetBlockNumber(), BufferGetPage(), CHECK_FOR_INTERRUPTS, BlockRangeReadStreamPrivate::current_blocknum, HashIndexStat::dead_items, elog, ereport, errcode(), errmsg, ERROR, fb(), Float8GetDatum(), HashIndexStat::free_space, get_call_result_type(), GetAccessStrategy(), GetHashPageStats(), HASH_METAPAGE, HASH_READ, HashPageOpaqueData::hasho_flag, HashPageGetMeta, HashPageGetOpaque, heap_form_tuple(), HeapTupleGetDatum(), Int32GetDatum(), Int64GetDatum(), InvalidBuffer, IS_HASH, IS_INDEX, BlockRangeReadStreamPrivate::last_exclusive, LH_BITMAP_PAGE, LH_BUCKET_PAGE, LH_META_PAGE, LH_OVERFLOW_PAGE, LH_PAGE_TYPE, LH_UNUSED_PAGE, HashIndexStat::live_items, LockBuffer(), MAIN_FORKNUM, MAXALIGN, HashIndexStat::overflow_pages, PageGetSpecialSize(), PageIsNew(), PG_GETARG_OID, PG_RETURN_DATUM, RelationData::rd_index, read_stream_begin_relation(), read_stream_end(), READ_STREAM_FULL, read_stream_next_buffer(), READ_STREAM_USE_BATCHING, relation_close(), RELATION_IS_OTHER_TEMP, relation_open(), RelationGetNumberOfBlocks, RelationGetRelationName, HashIndexStat::space_per_page, TYPEFUNC_COMPOSITE, UnlockReleaseBuffer(), HashIndexStat::unused_pages, values, and HashIndexStat::version.

pgstatindex()

Datum pgstatindex

(

PG_FUNCTION_ARGS

)

Definition at line 143 of file pgstatindex.c.

{
    text       *relname = PG_GETARG_TEXT_PP(0);
    Relation    rel;
    RangeVar   *relrv;
 
    if (!superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to use pgstattuple functions")));
 
    relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
    rel = relation_openrv(relrv, AccessShareLock);
 
    PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
}

References AccessShareLock, ereport, errcode(), errmsg, ERROR, fb(), makeRangeVarFromNameList(), PG_GETARG_TEXT_PP, PG_RETURN_DATUM, pgstatindex_impl(), relation_openrv(), relname, superuser(), and textToQualifiedNameList().

pgstatindex_impl()

static Datum pgstatindex_impl ( Relation  rel, FunctionCallInfo  fcinfo  )

static

Definition at line 214 of file pgstatindex.c.

{
    Datum       result;
    BlockNumber nblocks;
    BlockNumber blkno;
    BTIndexStat indexStat;
    BufferAccessStrategy bstrategy = GetAccessStrategy(BAS_BULKREAD);
    BlockRangeReadStreamPrivate p;
    ReadStream *stream;
    BlockNumber startblk;
 
    if (!IS_INDEX(rel) || !IS_BTREE(rel))
        ereport(ERROR,
                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                 errmsg("relation \"%s\" is not a btree index",
                        RelationGetRelationName(rel))));
 
    /*
     * Reject attempts to read non-local temporary relations; we would be
     * likely to get wrong data since we have no visibility into the owning
     * session's local buffers.
     */
    if (RELATION_IS_OTHER_TEMP(rel))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("cannot access temporary tables of other sessions")));
 
    /*
     * A !indisready index could lead to ERRCODE_DATA_CORRUPTED later, so exit
     * early.  We're capable of assessing an indisready&&!indisvalid index,
     * but the results could be confusing.  For example, the index's size
     * could be too low for a valid index of the table.
     */
    if (!rel->rd_index->indisvalid)
        ereport(ERROR,
                (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                 errmsg("index \"%s\" is not valid",
                        RelationGetRelationName(rel))));
 
    /*
     * Read metapage
     */
    {
        Buffer      buffer = ReadBufferExtended(rel, MAIN_FORKNUM, 0, RBM_NORMAL, bstrategy);
        Page        page = BufferGetPage(buffer);
        BTMetaPageData *metad = BTPageGetMeta(page);
 
        indexStat.version = metad->btm_version;
        indexStat.level = metad->btm_level;
        indexStat.root_blkno = metad->btm_root;
 
        ReleaseBuffer(buffer);
    }
 
    /* -- init counters -- */
    indexStat.internal_pages = 0;
    indexStat.leaf_pages = 0;
    indexStat.empty_pages = 0;
    indexStat.deleted_pages = 0;
 
    indexStat.max_avail = 0;
    indexStat.free_space = 0;
 
    indexStat.fragments = 0;
 
    /*
     * Scan all blocks except the metapage (0th page) using streaming reads
     */
    nblocks = RelationGetNumberOfBlocks(rel);
    startblk = BTREE_METAPAGE + 1;
 
    p.current_blocknum = startblk;
    p.last_exclusive = nblocks;
 
    /*
     * It is safe to use batchmode as block_range_read_stream_cb takes no
     * locks.
     */
    stream = read_stream_begin_relation(READ_STREAM_FULL |
                                        READ_STREAM_USE_BATCHING,
                                        bstrategy,
                                        rel,
                                        MAIN_FORKNUM,
                                        block_range_read_stream_cb,
                                        &p,
                                        0);
 
    for (blkno = startblk; blkno < nblocks; blkno++)
    {
        Buffer      buffer;
        Page        page;
        BTPageOpaque opaque;
 
        CHECK_FOR_INTERRUPTS();
 
        buffer = read_stream_next_buffer(stream, NULL);
        LockBuffer(buffer, BUFFER_LOCK_SHARE);
 
        page = BufferGetPage(buffer);
        opaque = BTPageGetOpaque(page);
 
        /*
         * Determine page type, and update totals.
         *
         * Note that we arbitrarily bucket deleted pages together without
         * considering if they're leaf pages or internal pages.
         */
        if (P_ISDELETED(opaque))
            indexStat.deleted_pages++;
        else if (P_IGNORE(opaque))
            indexStat.empty_pages++;    /* this is the "half dead" state */
        else if (P_ISLEAF(opaque))
        {
            int         max_avail;
 
            max_avail = BLCKSZ - (BLCKSZ - ((PageHeader) page)->pd_special + SizeOfPageHeaderData);
            indexStat.max_avail += max_avail;
            indexStat.free_space += PageGetExactFreeSpace(page);
 
            indexStat.leaf_pages++;
 
            /*
             * If the next leaf is on an earlier block, it means a
             * fragmentation.
             */
            if (opaque->btpo_next != P_NONE && opaque->btpo_next < blkno)
                indexStat.fragments++;
        }
        else
            indexStat.internal_pages++;
 
        UnlockReleaseBuffer(buffer);
    }
 
    Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
    read_stream_end(stream);
 
    relation_close(rel, AccessShareLock);
 
    /*----------------------------
     * Build a result tuple
     *----------------------------
     */
    {
        TupleDesc   tupleDesc;
        int         j;
        char       *values[10];
        HeapTuple   tuple;
 
        /* Build a tuple descriptor for our result type */
        if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
            elog(ERROR, "return type must be a row type");
 
        j = 0;
        values[j++] = psprintf("%d", indexStat.version);
        values[j++] = psprintf("%d", indexStat.level);
        values[j++] = psprintf(INT64_FORMAT,
                               (1 + /* include the metapage in index_size */
                                indexStat.leaf_pages +
                                indexStat.internal_pages +
                                indexStat.deleted_pages +
                                indexStat.empty_pages) * BLCKSZ);
        values[j++] = psprintf("%u", indexStat.root_blkno);
        values[j++] = psprintf(INT64_FORMAT, indexStat.internal_pages);
        values[j++] = psprintf(INT64_FORMAT, indexStat.leaf_pages);
        values[j++] = psprintf(INT64_FORMAT, indexStat.empty_pages);
        values[j++] = psprintf(INT64_FORMAT, indexStat.deleted_pages);
        if (indexStat.max_avail > 0)
            values[j++] = psprintf("%.2f",
                                   100.0 - (double) indexStat.free_space / (double) indexStat.max_avail * 100.0);
        else
            values[j++] = pstrdup("NaN");
        if (indexStat.leaf_pages > 0)
            values[j++] = psprintf("%.2f",
                                   (double) indexStat.fragments / (double) indexStat.leaf_pages * 100.0);
        else
            values[j++] = pstrdup("NaN");
 
        tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
                                       values);
 
        result = HeapTupleGetDatum(tuple);
    }
 
    return result;
}

References AccessShareLock, Assert, BAS_BULKREAD, block_range_read_stream_cb(), BTPageGetMeta, BTPageGetOpaque, BTPageOpaqueData::btpo_next, BTREE_METAPAGE, BUFFER_LOCK_SHARE, BufferGetPage(), BuildTupleFromCStrings(), CHECK_FOR_INTERRUPTS, BlockRangeReadStreamPrivate::current_blocknum, elog, ereport, errcode(), errmsg, ERROR, fb(), get_call_result_type(), GetAccessStrategy(), HeapTupleGetDatum(), INT64_FORMAT, InvalidBuffer, IS_BTREE, IS_INDEX, j, BlockRangeReadStreamPrivate::last_exclusive, LockBuffer(), MAIN_FORKNUM, P_IGNORE, P_ISDELETED, P_ISLEAF, P_NONE, PageGetExactFreeSpace(), psprintf(), pstrdup(), RBM_NORMAL, RelationData::rd_index, read_stream_begin_relation(), read_stream_end(), READ_STREAM_FULL, read_stream_next_buffer(), READ_STREAM_USE_BATCHING, ReadBufferExtended(), relation_close(), RELATION_IS_OTHER_TEMP, RelationGetNumberOfBlocks, RelationGetRelationName, ReleaseBuffer(), SizeOfPageHeaderData, TupleDescGetAttInMetadata(), TYPEFUNC_COMPOSITE, UnlockReleaseBuffer(), and values.

Referenced by pgstatindex(), pgstatindex_v1_5(), pgstatindexbyid(), and pgstatindexbyid_v1_5().

pgstatindex_v1_5()

Datum pgstatindex_v1_5

(

PG_FUNCTION_ARGS

)

Definition at line 168 of file pgstatindex.c.

{
    text       *relname = PG_GETARG_TEXT_PP(0);
    Relation    rel;
    RangeVar   *relrv;
 
    relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
    rel = relation_openrv(relrv, AccessShareLock);
 
    PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
}

References AccessShareLock, fb(), makeRangeVarFromNameList(), PG_GETARG_TEXT_PP, PG_RETURN_DATUM, pgstatindex_impl(), relation_openrv(), relname, and textToQualifiedNameList().

pgstatindexbyid()

Datum pgstatindexbyid

(

PG_FUNCTION_ARGS

)

Definition at line 186 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
    Relation    rel;
 
    if (!superuser())
        ereport(ERROR,
                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                 errmsg("must be superuser to use pgstattuple functions")));
 
    rel = relation_open(relid, AccessShareLock);
 
    PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
}

References AccessShareLock, ereport, errcode(), errmsg, ERROR, fb(), PG_GETARG_OID, PG_RETURN_DATUM, pgstatindex_impl(), relation_open(), and superuser().

pgstatindexbyid_v1_5()

Datum pgstatindexbyid_v1_5

(

PG_FUNCTION_ARGS

)

Definition at line 203 of file pgstatindex.c.

{
    Oid         relid = PG_GETARG_OID(0);
    Relation    rel;
 
    rel = relation_open(relid, AccessShareLock);
 
    PG_RETURN_DATUM(pgstatindex_impl(rel, fcinfo));
}

References AccessShareLock, PG_GETARG_OID, PG_RETURN_DATUM, pgstatindex_impl(), and relation_open().