Quelle  pgstat_archiver.c

/* -------------------------------------------------------------------------
 *
 * pgstat_archiver.c
 *   Implementation of archiver statistics.
 *
 * This file contains the implementation of archiver statistics. It is kept
 * separate from pgstat.c to enforce the line between the statistics access /
 * storage implementation and the details about individual types of
 * statistics.
 *
 * Copyright (c) 2001-2025, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *   src/backend/utils/activity/pgstat_archiver.c
 * -------------------------------------------------------------------------
 */

#include "postgres.h"

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


/*
 * Report archiver statistics
 */
void
pgstat_report_archiver(const char *xlog, bool failed)
{
 PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;
 TimestampTz now = GetCurrentTimestamp();

 pgstat_begin_changecount_write(&stats_shmem->changecount);

 if (failed)
 {
  ++stats_shmem->stats.failed_count;
  memcpy(&stats_shmem->stats.last_failed_wal, xlog,
      sizeof(stats_shmem->stats.last_failed_wal));
  stats_shmem->stats.last_failed_timestamp = now;
 }
 else
 {
  ++stats_shmem->stats.archived_count;
  memcpy(&stats_shmem->stats.last_archived_wal, xlog,
      sizeof(stats_shmem->stats.last_archived_wal));
  stats_shmem->stats.last_archived_timestamp = now;
 }

 pgstat_end_changecount_write(&stats_shmem->changecount);
}

/*
 * Support function for the SQL-callable pgstat* functions. Returns
 * a pointer to the archiver statistics struct.
 */
PgStat_ArchiverStats *
pgstat_fetch_stat_archiver(void)
{
 pgstat_snapshot_fixed(PGSTAT_KIND_ARCHIVER);

 return &pgStatLocal.snapshot.archiver;
}

void
pgstat_archiver_init_shmem_cb(void *stats)
{
 PgStatShared_Archiver *stats_shmem = (PgStatShared_Archiver *) stats;

 LWLockInitialize(&stats_shmem->lock, LWTRANCHE_PGSTATS_DATA);
}

void
pgstat_archiver_reset_all_cb(TimestampTz ts)
{
 PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;

 /* see explanation above PgStatShared_Archiver for the reset protocol */
 LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
 pgstat_copy_changecounted_stats(&stats_shmem->reset_offset,
         &stats_shmem->stats,
         sizeof(stats_shmem->stats),
         &stats_shmem->changecount);
 stats_shmem->stats.stat_reset_timestamp = ts;
 LWLockRelease(&stats_shmem->lock);
}

void
pgstat_archiver_snapshot_cb(void)
{
 PgStatShared_Archiver *stats_shmem = &pgStatLocal.shmem->archiver;
 PgStat_ArchiverStats *stat_snap = &pgStatLocal.snapshot.archiver;
 PgStat_ArchiverStats *reset_offset = &stats_shmem->reset_offset;
 PgStat_ArchiverStats reset;

 pgstat_copy_changecounted_stats(stat_snap,
         &stats_shmem->stats,
         sizeof(stats_shmem->stats),
         &stats_shmem->changecount);

 LWLockAcquire(&stats_shmem->lock, LW_SHARED);
 memcpy(&reset, reset_offset, sizeof(stats_shmem->stats));
 LWLockRelease(&stats_shmem->lock);

 /* compensate by reset offsets */
 if (stat_snap->archived_count == reset.archived_count)
 {
  stat_snap->last_archived_wal[0] = 0;
  stat_snap->last_archived_timestamp = 0;
 }
 stat_snap->archived_count -= reset.archived_count;

 if (stat_snap->failed_count == reset.failed_count)
 {
  stat_snap->last_failed_wal[0] = 0;
  stat_snap->last_failed_timestamp = 0;
 }
 stat_snap->failed_count -= reset.failed_count;
}