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pgstat_database.c
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1 /* -------------------------------------------------------------------------
2  *
3  * pgstat_database.c
4  * Implementation of database statistics.
5  *
6  * This file contains the implementation of database 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) 2001-2024, PostgreSQL Global Development Group
12  *
13  * IDENTIFICATION
14  * src/backend/utils/activity/pgstat_database.c
15  * -------------------------------------------------------------------------
16  */
17 
18 #include "postgres.h"
19 
20 #include "utils/pgstat_internal.h"
21 #include "utils/timestamp.h"
22 #include "storage/procsignal.h"
23 
24 
25 static bool pgstat_should_report_connstat(void);
26 
27 
33 
34 
35 static int pgStatXactCommit = 0;
36 static int pgStatXactRollback = 0;
38 
39 
40 /*
41  * Remove entry for the database being dropped.
42  */
43 void
45 {
47 }
48 
49 /*
50  * Called from autovacuum.c to report startup of an autovacuum process.
51  * We are called before InitPostgres is done, so can't rely on MyDatabaseId;
52  * the db OID must be passed in, instead.
53  */
54 void
56 {
57  PgStat_EntryRef *entry_ref;
58  PgStatShared_Database *dbentry;
59 
60  /* can't get here in single user mode */
62 
63  /*
64  * End-of-vacuum is reported instantly. Report the start the same way for
65  * consistency. Vacuum doesn't run frequently and is a long-lasting
66  * operation so it doesn't matter if we get blocked here a little.
67  */
69  dboid, InvalidOid, false);
70 
71  dbentry = (PgStatShared_Database *) entry_ref->shared_stats;
73 
74  pgstat_unlock_entry(entry_ref);
75 }
76 
77 /*
78  * Report a Hot Standby recovery conflict.
79  */
80 void
82 {
83  PgStat_StatDBEntry *dbentry;
84 
87  return;
88 
90 
91  switch (reason)
92  {
94 
95  /*
96  * Since we drop the information about the database as soon as it
97  * replicates, there is no point in counting these conflicts.
98  */
99  break;
101  dbentry->conflict_tablespace++;
102  break;
104  dbentry->conflict_lock++;
105  break;
107  dbentry->conflict_snapshot++;
108  break;
110  dbentry->conflict_bufferpin++;
111  break;
113  dbentry->conflict_logicalslot++;
114  break;
116  dbentry->conflict_startup_deadlock++;
117  break;
118  }
119 }
120 
121 /*
122  * Report a detected deadlock.
123  */
124 void
126 {
127  PgStat_StatDBEntry *dbent;
128 
129  if (!pgstat_track_counts)
130  return;
131 
133  dbent->deadlocks++;
134 }
135 
136 /*
137  * Report one or more checksum failures.
138  */
139 void
141 {
142  PgStat_EntryRef *entry_ref;
143  PgStatShared_Database *sharedent;
144 
145  if (!pgstat_track_counts)
146  return;
147 
148  /*
149  * Update the shared stats directly - checksum failures should never be
150  * common enough for that to be a problem.
151  */
152  entry_ref =
154 
155  sharedent = (PgStatShared_Database *) entry_ref->shared_stats;
156  sharedent->stats.checksum_failures += failurecount;
158 
159  pgstat_unlock_entry(entry_ref);
160 }
161 
162 /*
163  * Report one checksum failure in the current database.
164  */
165 void
167 {
169 }
170 
171 /*
172  * Report creation of temporary file.
173  */
174 void
175 pgstat_report_tempfile(size_t filesize)
176 {
177  PgStat_StatDBEntry *dbent;
178 
179  if (!pgstat_track_counts)
180  return;
181 
183  dbent->temp_bytes += filesize;
184  dbent->temp_files++;
185 }
186 
187 /*
188  * Notify stats system of a new connection.
189  */
190 void
192 {
193  PgStat_StatDBEntry *dbentry;
194 
196  return;
197 
199 
201  dbentry->sessions++;
202 }
203 
204 /*
205  * Notify the stats system of a disconnect.
206  */
207 void
209 {
210  PgStat_StatDBEntry *dbentry;
211 
213  return;
214 
216 
217  switch (pgStatSessionEndCause)
218  {
219  case DISCONNECT_NOT_YET:
220  case DISCONNECT_NORMAL:
221  /* we don't collect these */
222  break;
224  dbentry->sessions_abandoned++;
225  break;
226  case DISCONNECT_FATAL:
227  dbentry->sessions_fatal++;
228  break;
229  case DISCONNECT_KILLED:
230  dbentry->sessions_killed++;
231  break;
232  }
233 }
234 
235 /*
236  * Support function for the SQL-callable pgstat* functions. Returns
237  * the collected statistics for one database or NULL. NULL doesn't mean
238  * that the database doesn't exist, just that there are no statistics, so the
239  * caller is better off to report ZERO instead.
240  */
243 {
244  return (PgStat_StatDBEntry *)
246 }
247 
248 void
249 AtEOXact_PgStat_Database(bool isCommit, bool parallel)
250 {
251  /* Don't count parallel worker transaction stats */
252  if (!parallel)
253  {
254  /*
255  * Count transaction commit or abort. (We use counters, not just
256  * bools, in case the reporting message isn't sent right away.)
257  */
258  if (isCommit)
260  else
262  }
263 }
264 
265 /*
266  * Subroutine for pgstat_report_stat(): Handle xact commit/rollback and I/O
267  * timings.
268  */
269 void
271 {
272  PgStat_StatDBEntry *dbentry;
273 
274  /*
275  * If not connected to a database yet, don't attribute time to "shared
276  * state" (InvalidOid is used to track stats for shared relations, etc.).
277  */
278  if (!OidIsValid(MyDatabaseId))
279  return;
280 
282 
283  /*
284  * Accumulate xact commit/rollback and I/O timings to stats entry of the
285  * current database.
286  */
287  dbentry->xact_commit += pgStatXactCommit;
288  dbentry->xact_rollback += pgStatXactRollback;
291 
293  {
294  long secs;
295  int usecs;
296 
297  /*
298  * pgLastSessionReportTime is initialized to MyStartTimestamp by
299  * pgstat_report_connect().
300  */
301  TimestampDifference(pgLastSessionReportTime, ts, &secs, &usecs);
303  dbentry->session_time += (PgStat_Counter) secs * 1000000 + usecs;
304  dbentry->active_time += pgStatActiveTime;
306  }
307 
308  pgStatXactCommit = 0;
309  pgStatXactRollback = 0;
312  pgStatActiveTime = 0;
314 }
315 
316 /*
317  * We report session statistics only for normal backend processes. Parallel
318  * workers run in parallel, so they don't contribute to session times, even
319  * though they use CPU time. Walsender processes could be considered here,
320  * but they have different session characteristics from normal backends (for
321  * example, they are always "active"), so they would skew session statistics.
322  */
323 static bool
325 {
326  return MyBackendType == B_BACKEND;
327 }
328 
329 /*
330  * Find or create a local PgStat_StatDBEntry entry for dboid.
331  */
334 {
335  PgStat_EntryRef *entry_ref;
336 
337  /*
338  * This should not report stats on database objects before having
339  * connected to a database.
340  */
342 
344  NULL);
345 
346  return entry_ref->pending;
347 }
348 
349 /*
350  * Reset the database's reset timestamp, without resetting the contents of the
351  * database stats.
352  */
353 void
355 {
356  PgStat_EntryRef *dbref;
357  PgStatShared_Database *dbentry;
358 
360  false);
361 
362  dbentry = (PgStatShared_Database *) dbref->shared_stats;
363  dbentry->stats.stat_reset_timestamp = ts;
364 
365  pgstat_unlock_entry(dbref);
366 }
367 
368 /*
369  * Flush out pending stats for the entry
370  *
371  * If nowait is true, this function returns false if lock could not
372  * immediately acquired, otherwise true is returned.
373  */
374 bool
376 {
377  PgStatShared_Database *sharedent;
378  PgStat_StatDBEntry *pendingent;
379 
380  pendingent = (PgStat_StatDBEntry *) entry_ref->pending;
381  sharedent = (PgStatShared_Database *) entry_ref->shared_stats;
382 
383  if (!pgstat_lock_entry(entry_ref, nowait))
384  return false;
385 
386 #define PGSTAT_ACCUM_DBCOUNT(item) \
387  (sharedent)->stats.item += (pendingent)->item
388 
389  PGSTAT_ACCUM_DBCOUNT(xact_commit);
390  PGSTAT_ACCUM_DBCOUNT(xact_rollback);
391  PGSTAT_ACCUM_DBCOUNT(blocks_fetched);
392  PGSTAT_ACCUM_DBCOUNT(blocks_hit);
393 
394  PGSTAT_ACCUM_DBCOUNT(tuples_returned);
395  PGSTAT_ACCUM_DBCOUNT(tuples_fetched);
396  PGSTAT_ACCUM_DBCOUNT(tuples_inserted);
397  PGSTAT_ACCUM_DBCOUNT(tuples_updated);
398  PGSTAT_ACCUM_DBCOUNT(tuples_deleted);
399 
400  /* last_autovac_time is reported immediately */
401  Assert(pendingent->last_autovac_time == 0);
402 
403  PGSTAT_ACCUM_DBCOUNT(conflict_tablespace);
404  PGSTAT_ACCUM_DBCOUNT(conflict_lock);
405  PGSTAT_ACCUM_DBCOUNT(conflict_snapshot);
406  PGSTAT_ACCUM_DBCOUNT(conflict_logicalslot);
407  PGSTAT_ACCUM_DBCOUNT(conflict_bufferpin);
408  PGSTAT_ACCUM_DBCOUNT(conflict_startup_deadlock);
409 
410  PGSTAT_ACCUM_DBCOUNT(temp_bytes);
411  PGSTAT_ACCUM_DBCOUNT(temp_files);
412  PGSTAT_ACCUM_DBCOUNT(deadlocks);
413 
414  /* checksum failures are reported immediately */
415  Assert(pendingent->checksum_failures == 0);
416  Assert(pendingent->last_checksum_failure == 0);
417 
418  PGSTAT_ACCUM_DBCOUNT(blk_read_time);
419  PGSTAT_ACCUM_DBCOUNT(blk_write_time);
420 
421  PGSTAT_ACCUM_DBCOUNT(sessions);
422  PGSTAT_ACCUM_DBCOUNT(session_time);
423  PGSTAT_ACCUM_DBCOUNT(active_time);
424  PGSTAT_ACCUM_DBCOUNT(idle_in_transaction_time);
425  PGSTAT_ACCUM_DBCOUNT(sessions_abandoned);
426  PGSTAT_ACCUM_DBCOUNT(sessions_fatal);
427  PGSTAT_ACCUM_DBCOUNT(sessions_killed);
428 #undef PGSTAT_ACCUM_DBCOUNT
429 
430  pgstat_unlock_entry(entry_ref);
431 
432  memset(pendingent, 0, sizeof(*pendingent));
433 
434  return true;
435 }
436 
437 void
439 {
440  ((PgStatShared_Database *) header)->stats.stat_reset_timestamp = ts;
441 }
void TimestampDifference(TimestampTz start_time, TimestampTz stop_time, long *secs, int *microsecs)
Definition: timestamp.c:1731
TimestampTz GetCurrentTimestamp(void)
Definition: timestamp.c:1655
#define OidIsValid(objectId)
Definition: c.h:764
int64 TimestampTz
Definition: timestamp.h:39
bool IsUnderPostmaster
Definition: globals.c:116
TimestampTz MyStartTimestamp
Definition: globals.c:47
Oid MyDatabaseId
Definition: globals.c:90
Assert(fmt[strlen(fmt) - 1] !='\n')
@ B_BACKEND
Definition: miscadmin.h:331
BackendType MyBackendType
Definition: miscinit.c:64
bool pgstat_track_counts
Definition: pgstat.c:187
void * pgstat_fetch_entry(PgStat_Kind kind, Oid dboid, Oid objoid)
Definition: pgstat.c:815
PgStat_EntryRef * pgstat_prep_pending_entry(PgStat_Kind kind, Oid dboid, Oid objoid, bool *created_entry)
Definition: pgstat.c:1108
SessionEndType
Definition: pgstat.h:77
@ DISCONNECT_NOT_YET
Definition: pgstat.h:78
@ DISCONNECT_FATAL
Definition: pgstat.h:81
@ DISCONNECT_KILLED
Definition: pgstat.h:82
@ DISCONNECT_CLIENT_EOF
Definition: pgstat.h:80
@ DISCONNECT_NORMAL
Definition: pgstat.h:79
@ PGSTAT_KIND_DATABASE
Definition: pgstat.h:41
int64 PgStat_Counter
Definition: pgstat.h:89
static bool pgstat_should_report_connstat(void)
PgStat_Counter pgStatActiveTime
PgStat_Counter pgStatBlockReadTime
void pgstat_report_autovac(Oid dboid)
void pgstat_database_reset_timestamp_cb(PgStatShared_Common *header, TimestampTz ts)
void pgstat_report_connect(Oid dboid)
PgStat_Counter pgStatBlockWriteTime
void pgstat_report_checksum_failures_in_db(Oid dboid, int failurecount)
void pgstat_report_checksum_failure(void)
static PgStat_Counter pgLastSessionReportTime
static int pgStatXactCommit
void AtEOXact_PgStat_Database(bool isCommit, bool parallel)
void pgstat_report_deadlock(void)
void pgstat_report_recovery_conflict(int reason)
void pgstat_update_dbstats(TimestampTz ts)
PgStat_StatDBEntry * pgstat_prep_database_pending(Oid dboid)
PgStat_Counter pgStatTransactionIdleTime
SessionEndType pgStatSessionEndCause
void pgstat_drop_database(Oid databaseid)
PgStat_StatDBEntry * pgstat_fetch_stat_dbentry(Oid dboid)
void pgstat_reset_database_timestamp(Oid dboid, TimestampTz ts)
void pgstat_report_disconnect(Oid dboid)
#define PGSTAT_ACCUM_DBCOUNT(item)
static int pgStatXactRollback
bool pgstat_database_flush_cb(PgStat_EntryRef *entry_ref, bool nowait)
void pgstat_report_tempfile(size_t filesize)
void pgstat_unlock_entry(PgStat_EntryRef *entry_ref)
Definition: pgstat_shmem.c:604
bool pgstat_lock_entry(PgStat_EntryRef *entry_ref, bool nowait)
Definition: pgstat_shmem.c:576
PgStat_EntryRef * pgstat_get_entry_ref_locked(PgStat_Kind kind, Oid dboid, Oid objoid, bool nowait)
Definition: pgstat_shmem.c:613
void pgstat_drop_transactional(PgStat_Kind kind, Oid dboid, Oid objoid)
Definition: pgstat_xact.c:380
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
@ PROCSIG_RECOVERY_CONFLICT_BUFFERPIN
Definition: procsignal.h:47
@ PROCSIG_RECOVERY_CONFLICT_LOCK
Definition: procsignal.h:44
@ PROCSIG_RECOVERY_CONFLICT_LOGICALSLOT
Definition: procsignal.h:46
@ PROCSIG_RECOVERY_CONFLICT_DATABASE
Definition: procsignal.h:42
@ PROCSIG_RECOVERY_CONFLICT_SNAPSHOT
Definition: procsignal.h:45
@ PROCSIG_RECOVERY_CONFLICT_TABLESPACE
Definition: procsignal.h:43
@ PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK
Definition: procsignal.h:48
PgStat_StatDBEntry stats
PgStatShared_Common * shared_stats
PgStat_Counter blk_write_time
Definition: pgstat.h:347
PgStat_Counter xact_rollback
Definition: pgstat.h:326
PgStat_Counter conflict_startup_deadlock
Definition: pgstat.h:340
PgStat_Counter conflict_lock
Definition: pgstat.h:336
TimestampTz stat_reset_timestamp
Definition: pgstat.h:356
PgStat_Counter conflict_snapshot
Definition: pgstat.h:337
PgStat_Counter sessions_fatal
Definition: pgstat.h:353
TimestampTz last_checksum_failure
Definition: pgstat.h:345
PgStat_Counter blk_read_time
Definition: pgstat.h:346
PgStat_Counter xact_commit
Definition: pgstat.h:325
TimestampTz last_autovac_time
Definition: pgstat.h:334
PgStat_Counter deadlocks
Definition: pgstat.h:343
PgStat_Counter temp_bytes
Definition: pgstat.h:342
PgStat_Counter session_time
Definition: pgstat.h:349
PgStat_Counter temp_files
Definition: pgstat.h:341
PgStat_Counter sessions_abandoned
Definition: pgstat.h:352
PgStat_Counter sessions
Definition: pgstat.h:348
PgStat_Counter active_time
Definition: pgstat.h:350
PgStat_Counter conflict_bufferpin
Definition: pgstat.h:339
PgStat_Counter idle_in_transaction_time
Definition: pgstat.h:351
PgStat_Counter conflict_logicalslot
Definition: pgstat.h:338
PgStat_Counter sessions_killed
Definition: pgstat.h:354
PgStat_Counter checksum_failures
Definition: pgstat.h:344
PgStat_Counter conflict_tablespace
Definition: pgstat.h:335