pgstat_slru.c File Reference

#include "postgres.h"
#include "utils/pgstat_internal.h"
#include "utils/timestamp.h"

Include dependency graph for pgstat_slru.c:

Go to the source code of this file.

Macros
#define	PGSTAT_COUNT_SLRU(stat)
#define	SLRU_ACC(fld)   sharedent->fld += pendingent->fld

Functions
static PgStat_SLRUStats *	get_slru_entry (int slru_idx)
static void	pgstat_reset_slru_counter_internal (int index, TimestampTz ts)
void	pgstat_reset_slru (const char *name)
PgStat_SLRUStats *	pgstat_fetch_slru (void)
const char *	pgstat_get_slru_name (int slru_idx)
int	pgstat_get_slru_index (const char *name)
bool	pgstat_slru_flush_cb (bool nowait)
void	pgstat_slru_init_shmem_cb (void *stats)
void	pgstat_slru_reset_all_cb (TimestampTz ts)
void	pgstat_slru_snapshot_cb (void)

Variables
static PgStat_SLRUStats	pending_SLRUStats [SLRU_NUM_ELEMENTS]
static bool	have_slrustats = false

Macro Definition Documentation

PGSTAT_COUNT_SLRU

#define PGSTAT_COUNT_SLRU

(

stat

)

Value:

void												\
CppConcat(pgstat_count_slru_,stat)(int slru_idx)    \
{                                                   \
	get_slru_entry(slru_idx)->stat += 1;           \
}

Definition at line 58 of file pgstat_slru.c.

{                                                   \
	get_slru_entry(slru_idx)->stat += 1;           \
}

SLRU_ACC

#define SLRU_ACC

(

fld

)

sharedent->fld += pendingent->fld

Function Documentation

get_slru_entry()

static PgStat_SLRUStats * get_slru_entry ( int  slru_idx )

inlinestatic

Definition at line 212 of file pgstat_slru.c.

{
    pgstat_assert_is_up();
 
    /*
     * The postmaster should never register any SLRU statistics counts; if it
     * did, the counts would be duplicated into child processes via fork().
     */
    Assert(IsUnderPostmaster || !IsPostmasterEnvironment);
 
    Assert((slru_idx >= 0) && (slru_idx < SLRU_NUM_ELEMENTS));
 
    have_slrustats = true;
    pgstat_report_fixed = true;
 
    return &pending_SLRUStats[slru_idx];
}

References Assert, fb(), have_slrustats, IsPostmasterEnvironment, IsUnderPostmaster, pending_SLRUStats, pgstat_assert_is_up, pgstat_report_fixed, and SLRU_NUM_ELEMENTS.

pgstat_fetch_slru()

PgStat_SLRUStats * pgstat_fetch_slru

(

void

)

Definition at line 91 of file pgstat_slru.c.

{
    pgstat_snapshot_fixed(PGSTAT_KIND_SLRU);
 
    return pgStatLocal.snapshot.slru;
}

References PGSTAT_KIND_SLRU, pgstat_snapshot_fixed(), pgStatLocal, PgStat_Snapshot::slru, and PgStat_LocalState::snapshot.

Referenced by pg_stat_get_slru().

pgstat_get_slru_index()

int pgstat_get_slru_index

(

const char *

name

)

Definition at line 118 of file pgstat_slru.c.

{
    int         i;
 
    Assert(name);
    for (i = 0; i < SLRU_NUM_ELEMENTS; i++)
    {
        if (strcmp(slru_names[i], name) == 0)
            return i;
    }
 
    /* return index of the last entry (which is the "other" one) */
    return (SLRU_NUM_ELEMENTS - 1);
}

References Assert, fb(), i, name, slru_names, and SLRU_NUM_ELEMENTS.

Referenced by pgstat_reset_slru(), and shmem_slru_init().

pgstat_get_slru_name()

const char * pgstat_get_slru_name

(

int

slru_idx

)

Definition at line 104 of file pgstat_slru.c.

{
    if (slru_idx < 0 || slru_idx >= SLRU_NUM_ELEMENTS)
        return NULL;
 
    return slru_names[slru_idx];
}

References fb(), slru_names, and SLRU_NUM_ELEMENTS.

Referenced by pg_stat_get_slru().

pgstat_reset_slru()

void pgstat_reset_slru

(

const char *

name

)

Definition at line 45 of file pgstat_slru.c.

{
    TimestampTz ts = GetCurrentTimestamp();
 
    Assert(name != NULL);
 
    pgstat_reset_slru_counter_internal(pgstat_get_slru_index(name), ts);
}

References Assert, fb(), GetCurrentTimestamp(), name, pgstat_get_slru_index(), and pgstat_reset_slru_counter_internal().

Referenced by pg_stat_reset_slru().

pgstat_reset_slru_counter_internal()

static void pgstat_reset_slru_counter_internal ( int  index, TimestampTz  ts  )

static

Definition at line 231 of file pgstat_slru.c.

{
    PgStatShared_SLRU *stats_shmem = &pgStatLocal.shmem->slru;
 
    LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
 
    memset(&stats_shmem->stats[index], 0, sizeof(PgStat_SLRUStats));
    stats_shmem->stats[index].stat_reset_timestamp = ts;
 
    LWLockRelease(&stats_shmem->lock);
}

References fb(), LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), pgStatLocal, PgStat_LocalState::shmem, and PgStat_ShmemControl::slru.

Referenced by pgstat_reset_slru(), and pgstat_slru_reset_all_cb().

pgstat_slru_flush_cb()

bool pgstat_slru_flush_cb

(

bool

nowait

)

Definition at line 140 of file pgstat_slru.c.

{
    PgStatShared_SLRU *stats_shmem = &pgStatLocal.shmem->slru;
    int         i;
 
    if (!have_slrustats)
        return false;
 
    if (!nowait)
        LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
    else if (!LWLockConditionalAcquire(&stats_shmem->lock, LW_EXCLUSIVE))
        return true;
 
    for (i = 0; i < SLRU_NUM_ELEMENTS; i++)
    {
        PgStat_SLRUStats *sharedent = &stats_shmem->stats[i];
        PgStat_SLRUStats *pendingent = &pending_SLRUStats[i];
 
#define SLRU_ACC(fld) sharedent->fld += pendingent->fld
        SLRU_ACC(blocks_zeroed);
        SLRU_ACC(blocks_hit);
        SLRU_ACC(blocks_read);
        SLRU_ACC(blocks_written);
        SLRU_ACC(blocks_exists);
        SLRU_ACC(flush);
        SLRU_ACC(truncate);
#undef SLRU_ACC
    }
 
    /* done, clear the pending entry */
    MemSet(pending_SLRUStats, 0, sizeof(pending_SLRUStats));
 
    LWLockRelease(&stats_shmem->lock);
 
    have_slrustats = false;
 
    return false;
}

References blocks_written, fb(), have_slrustats, i, LW_EXCLUSIVE, LWLockAcquire(), LWLockConditionalAcquire(), LWLockRelease(), MemSet, pending_SLRUStats, pgStatLocal, PgStat_LocalState::shmem, PgStat_ShmemControl::slru, SLRU_ACC, and SLRU_NUM_ELEMENTS.

pgstat_slru_init_shmem_cb()

void pgstat_slru_init_shmem_cb

(

void *

stats

)

Definition at line 180 of file pgstat_slru.c.

{
    PgStatShared_SLRU *stats_shmem = (PgStatShared_SLRU *) stats;
 
    LWLockInitialize(&stats_shmem->lock, LWTRANCHE_PGSTATS_DATA);
}

References fb(), and LWLockInitialize().

pgstat_slru_reset_all_cb()

void pgstat_slru_reset_all_cb

(

TimestampTz

ts

)

Definition at line 188 of file pgstat_slru.c.

{
    for (int i = 0; i < SLRU_NUM_ELEMENTS; i++)
        pgstat_reset_slru_counter_internal(i, ts);
}

References i, pgstat_reset_slru_counter_internal(), and SLRU_NUM_ELEMENTS.

pgstat_slru_snapshot_cb()

void pgstat_slru_snapshot_cb

(

void

)

Definition at line 195 of file pgstat_slru.c.

{
    PgStatShared_SLRU *stats_shmem = &pgStatLocal.shmem->slru;
 
    LWLockAcquire(&stats_shmem->lock, LW_SHARED);
 
    memcpy(pgStatLocal.snapshot.slru, &stats_shmem->stats,
           sizeof(stats_shmem->stats));
 
    LWLockRelease(&stats_shmem->lock);
}

References fb(), LW_SHARED, LWLockAcquire(), LWLockRelease(), memcpy(), pgStatLocal, PgStat_LocalState::shmem, PgStat_ShmemControl::slru, PgStat_Snapshot::slru, and PgStat_LocalState::snapshot.

Variable Documentation

have_slrustats

bool have_slrustats = false

static

Definition at line 35 of file pgstat_slru.c.

Referenced by get_slru_entry(), and pgstat_slru_flush_cb().

pending_SLRUStats

PgStat_SLRUStats pending_SLRUStats[SLRU_NUM_ELEMENTS]

static

Definition at line 34 of file pgstat_slru.c.

Referenced by get_slru_entry(), and pgstat_slru_flush_cb().