Age         Owner                  TLA  Line data    Source code

                                  1                 : /* -------------------------------------------------------------------------
                                  2                 :  *
                                  3                 :  * pgstat_checkpointer.c
                                  4                 :  *    Implementation of checkpoint statistics.
                                  5                 :  *
                                  6                 :  * This file contains the implementation of checkpoint statistics. It is kept
                                  7                 :  * separate from pgstat.c to enforce the line between the statistics access /
                                  8                 :  * storage implementation and the details about individual types of
                                  9                 :  * statistics.
                                 10                 :  *
                                 11                 :  * Copyright (c) 2001-2023, PostgreSQL Global Development Group
                                 12                 :  *
                                 13                 :  * IDENTIFICATION
                                 14                 :  *    src/backend/utils/activity/pgstat_checkpointer.c
                                 15                 :  * -------------------------------------------------------------------------
                                 16                 :  */
                                 17                 : 
                                 18                 : #include "postgres.h"
                                 19                 : 
                                 20                 : #include "utils/pgstat_internal.h"
                                 21                 : 
                                 22                 : 
                                 23                 : PgStat_CheckpointerStats PendingCheckpointerStats = {0};
                                 24                 : 
                                 25                 : 
                                 26                 : /*
                                 27                 :  * Report checkpointer and IO statistics
                                 28                 :  */
                                 29                 : void
  368 andres                     30 CBC        7107 : pgstat_report_checkpointer(void)
                                 31                 : {
                                 32                 :     /* We assume this initializes to zeroes */
                                 33                 :     static const PgStat_CheckpointerStats all_zeroes;
                                 34            7107 :     PgStatShared_Checkpointer *stats_shmem = &pgStatLocal.shmem->checkpointer;
                                 35                 : 
                                 36            7107 :     Assert(!pgStatLocal.shmem->is_shutdown);
                                 37            7107 :     pgstat_assert_is_up();
                                 38                 : 
                                 39                 :     /*
                                 40                 :      * This function can be called even if nothing at all has happened. In
                                 41                 :      * this case, avoid unnecessarily modifying the stats entry.
                                 42                 :      */
                                 43            7107 :     if (memcmp(&PendingCheckpointerStats, &all_zeroes,
                                 44                 :                sizeof(all_zeroes)) == 0)
  384                            45             617 :         return;
                                 46                 : 
  368                            47            6490 :     pgstat_begin_changecount_write(&stats_shmem->changecount);
                                 48                 : 
                                 49                 : #define CHECKPOINTER_ACC(fld) stats_shmem->stats.fld += PendingCheckpointerStats.fld
                                 50            6490 :     CHECKPOINTER_ACC(timed_checkpoints);
                                 51            6490 :     CHECKPOINTER_ACC(requested_checkpoints);
                                 52            6490 :     CHECKPOINTER_ACC(checkpoint_write_time);
                                 53            6490 :     CHECKPOINTER_ACC(checkpoint_sync_time);
                                 54            6490 :     CHECKPOINTER_ACC(buf_written_checkpoints);
                                 55            6490 :     CHECKPOINTER_ACC(buf_written_backend);
                                 56            6490 :     CHECKPOINTER_ACC(buf_fsync_backend);
                                 57                 : #undef CHECKPOINTER_ACC
                                 58                 : 
                                 59            6490 :     pgstat_end_changecount_write(&stats_shmem->changecount);
                                 60                 : 
                                 61                 :     /*
                                 62                 :      * Clear out the statistics buffer, so it can be re-used.
                                 63                 :      */
  384                            64           51920 :     MemSet(&PendingCheckpointerStats, 0, sizeof(PendingCheckpointerStats));
                                 65                 : 
                                 66                 :     /*
                                 67                 :      * Report IO statistics
                                 68                 :      */
   60 andres                     69 GNC        6490 :     pgstat_flush_io(false);
                                 70                 : }
                                 71                 : 
                                 72                 : /*
                                 73                 :  * pgstat_fetch_stat_checkpointer() -
  368 andres                     74 ECB             :  *
                                 75                 :  * Support function for the SQL-callable pgstat* functions. Returns
                                 76                 :  * a pointer to the checkpointer statistics struct.
                                 77                 :  */
                                 78                 : PgStat_CheckpointerStats *
  368 andres                     79 GIC          14 : pgstat_fetch_stat_checkpointer(void)
                                 80                 : {
                                 81              14 :     pgstat_snapshot_fixed(PGSTAT_KIND_CHECKPOINTER);
                                 82                 : 
                                 83              14 :     return &pgStatLocal.snapshot.checkpointer;
  368 andres                     84 ECB             : }
                                 85                 : 
                                 86                 : void
  368 andres                     87 GIC         442 : pgstat_checkpointer_reset_all_cb(TimestampTz ts)
  368 andres                     88 ECB             : {
  368 andres                     89 GIC         442 :     PgStatShared_Checkpointer *stats_shmem = &pgStatLocal.shmem->checkpointer;
                                 90                 : 
                                 91                 :     /* see explanation above PgStatShared_Checkpointer for the reset protocol */
  368 andres                     92 CBC         442 :     LWLockAcquire(&stats_shmem->lock, LW_EXCLUSIVE);
  368 andres                     93 GIC         442 :     pgstat_copy_changecounted_stats(&stats_shmem->reset_offset,
  368 andres                     94 CBC         442 :                                     &stats_shmem->stats,
                                 95                 :                                     sizeof(stats_shmem->stats),
                                 96                 :                                     &stats_shmem->changecount);
                                 97             442 :     LWLockRelease(&stats_shmem->lock);
                                 98             442 : }
  368 andres                     99 ECB             : 
                                100                 : void
  368 andres                    101 GIC        1002 : pgstat_checkpointer_snapshot_cb(void)
  368 andres                    102 ECB             : {
  368 andres                    103 CBC        1002 :     PgStatShared_Checkpointer *stats_shmem = &pgStatLocal.shmem->checkpointer;
  368 andres                    104 GIC        1002 :     PgStat_CheckpointerStats *reset_offset = &stats_shmem->reset_offset;
                                105                 :     PgStat_CheckpointerStats reset;
  368 andres                    106 ECB             : 
  368 andres                    107 GIC        1002 :     pgstat_copy_changecounted_stats(&pgStatLocal.snapshot.checkpointer,
  368 andres                    108 CBC        1002 :                                     &stats_shmem->stats,
  368 andres                    109 ECB             :                                     sizeof(stats_shmem->stats),
                                110                 :                                     &stats_shmem->changecount);
                                111                 : 
  368 andres                    112 CBC        1002 :     LWLockAcquire(&stats_shmem->lock, LW_SHARED);
                                113            1002 :     memcpy(&reset, reset_offset, sizeof(stats_shmem->stats));
  368 andres                    114 GIC        1002 :     LWLockRelease(&stats_shmem->lock);
                                115                 : 
                                116                 :     /* compensate by reset offsets */
  368 andres                    117 ECB             : #define CHECKPOINTER_COMP(fld) pgStatLocal.snapshot.checkpointer.fld -= reset.fld;
  368 andres                    118 CBC        1002 :     CHECKPOINTER_COMP(timed_checkpoints);
                                119            1002 :     CHECKPOINTER_COMP(requested_checkpoints);
  368 andres                    120 GIC        1002 :     CHECKPOINTER_COMP(checkpoint_write_time);
                                121            1002 :     CHECKPOINTER_COMP(checkpoint_sync_time);
                                122            1002 :     CHECKPOINTER_COMP(buf_written_checkpoints);
  368 andres                    123 CBC        1002 :     CHECKPOINTER_COMP(buf_written_backend);
                                124            1002 :     CHECKPOINTER_COMP(buf_fsync_backend);
  368 andres                    125 ECB             : #undef CHECKPOINTER_COMP
  368 andres                    126 CBC        1002 : }