PostgreSQL Source Code  git master
pgstat_bgwriter.c File Reference
#include "postgres.h"
#include "utils/pgstat_internal.h"
Include dependency graph for pgstat_bgwriter.c:

Go to the source code of this file.

Macros

#define BGWRITER_ACC(fld)   stats_shmem->stats.fld += PendingBgWriterStats.fld
 
#define BGWRITER_COMP(fld)   pgStatLocal.snapshot.bgwriter.fld -= reset.fld;
 

Functions

void pgstat_report_bgwriter (void)
 
PgStat_BgWriterStatspgstat_fetch_stat_bgwriter (void)
 
void pgstat_bgwriter_reset_all_cb (TimestampTz ts)
 
void pgstat_bgwriter_snapshot_cb (void)
 

Variables

PgStat_BgWriterStats PendingBgWriterStats = {0}
 

Macro Definition Documentation

◆ BGWRITER_ACC

#define BGWRITER_ACC (   fld)    stats_shmem->stats.fld += PendingBgWriterStats.fld

◆ BGWRITER_COMP

#define BGWRITER_COMP (   fld)    pgStatLocal.snapshot.bgwriter.fld -= reset.fld;

Function Documentation

◆ pgstat_bgwriter_reset_all_cb()

void pgstat_bgwriter_reset_all_cb ( TimestampTz  ts)

Definition at line 74 of file pgstat_bgwriter.c.

75 {
77 
78  /* see explanation above PgStatShared_BgWriter for the reset protocol */
79  LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
81  &stats_shmem->stats,
82  sizeof(stats_shmem->stats),
83  &stats_shmem->changecount);
84  stats_shmem->stats.stat_reset_timestamp = ts;
85  LWLockRelease(&stats_shmem->lock);
86 }
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1196
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1800
@ LW_EXCLUSIVE
Definition: lwlock.h:104
PgStat_LocalState pgStatLocal
Definition: pgstat.c:195
static void pgstat_copy_changecounted_stats(void *dst, void *src, size_t len, uint32 *cc)
PgStat_BgWriterStats reset_offset
PgStat_BgWriterStats stats
TimestampTz stat_reset_timestamp
Definition: pgstat.h:265
PgStat_ShmemControl * shmem
PgStatShared_BgWriter bgwriter

References PgStat_ShmemControl::bgwriter, PgStatShared_BgWriter::changecount, PgStatShared_BgWriter::lock, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), pgstat_copy_changecounted_stats(), pgStatLocal, PgStatShared_BgWriter::reset_offset, PgStat_LocalState::shmem, PgStat_BgWriterStats::stat_reset_timestamp, and PgStatShared_BgWriter::stats.

◆ pgstat_bgwriter_snapshot_cb()

void pgstat_bgwriter_snapshot_cb ( void  )

Definition at line 89 of file pgstat_bgwriter.c.

90 {
92  PgStat_BgWriterStats *reset_offset = &stats_shmem->reset_offset;
94 
96  &stats_shmem->stats,
97  sizeof(stats_shmem->stats),
98  &stats_shmem->changecount);
99 
100  LWLockAcquire(&stats_shmem->lock, LW_SHARED);
101  memcpy(&reset, reset_offset, sizeof(stats_shmem->stats));
102  LWLockRelease(&stats_shmem->lock);
103 
104  /* compensate by reset offsets */
105 #define BGWRITER_COMP(fld) pgStatLocal.snapshot.bgwriter.fld -= reset.fld;
106  BGWRITER_COMP(buf_written_clean);
107  BGWRITER_COMP(maxwritten_clean);
108  BGWRITER_COMP(buf_alloc);
109 #undef BGWRITER_COMP
110 }
@ LW_SHARED
Definition: lwlock.h:105
#define BGWRITER_COMP(fld)
void reset(void)
Definition: sql-declare.c:600
PgStat_Snapshot snapshot
PgStat_BgWriterStats bgwriter

References PgStat_ShmemControl::bgwriter, PgStat_Snapshot::bgwriter, BGWRITER_COMP, PgStatShared_BgWriter::changecount, PgStatShared_BgWriter::lock, LW_SHARED, LWLockAcquire(), LWLockRelease(), pgstat_copy_changecounted_stats(), pgStatLocal, reset(), PgStatShared_BgWriter::reset_offset, PgStat_LocalState::shmem, PgStat_LocalState::snapshot, and PgStatShared_BgWriter::stats.

◆ pgstat_fetch_stat_bgwriter()

◆ pgstat_report_bgwriter()

void pgstat_report_bgwriter ( void  )

Definition at line 30 of file pgstat_bgwriter.c.

31 {
33  static const PgStat_BgWriterStats all_zeroes;
34 
37 
38  /*
39  * This function can be called even if nothing at all has happened. In
40  * this case, avoid unnecessarily modifying the stats entry.
41  */
42  if (memcmp(&PendingBgWriterStats, &all_zeroes, sizeof(all_zeroes)) == 0)
43  return;
44 
46 
47 #define BGWRITER_ACC(fld) stats_shmem->stats.fld += PendingBgWriterStats.fld
48  BGWRITER_ACC(buf_written_clean);
49  BGWRITER_ACC(maxwritten_clean);
50  BGWRITER_ACC(buf_alloc);
51 #undef BGWRITER_ACC
52 
54 
55  /*
56  * Clear out the statistics buffer, so it can be re-used.
57  */
59 }
#define MemSet(start, val, len)
Definition: c.h:1008
Assert(fmt[strlen(fmt) - 1] !='\n')
#define BGWRITER_ACC(fld)
PgStat_BgWriterStats PendingBgWriterStats
static void pgstat_end_changecount_write(uint32 *cc)
#define pgstat_assert_is_up()
static void pgstat_begin_changecount_write(uint32 *cc)

References Assert(), PgStat_ShmemControl::bgwriter, BGWRITER_ACC, PgStatShared_BgWriter::changecount, PgStat_ShmemControl::is_shutdown, MemSet, PendingBgWriterStats, pgstat_assert_is_up, pgstat_begin_changecount_write(), pgstat_end_changecount_write(), pgStatLocal, and PgStat_LocalState::shmem.

Referenced by BackgroundWriterMain().

Variable Documentation

◆ PendingBgWriterStats

PgStat_BgWriterStats PendingBgWriterStats = {0}

Definition at line 23 of file pgstat_bgwriter.c.

Referenced by BgBufferSync(), and pgstat_report_bgwriter().