Hello,
I have addressed the reviews.
@Aleksander Alekseev thanks for reporting the issue. I have altered
the patch to respect the behavior of pg_stat_activity, specifically
[1]
> Another important point is that when a server process is asked to display any
> of these statistics,
> it first fetches the most recent report emitted by the collector process and
> then continues to use this snapshot
> for all statistical views and functions until the end of its current
> transaction.
> So the statistics will show static information as long as you continue the
> current transaction.
For the patch it means no computing of real-time values of
total_*_time. Here is an example to illustrate the new behavior:
=# begin;
=*# select total_active_time, total_idle_in_transaction_time from
pg_stat_activity where pid = pg_backend_pid();
total_active_time | total_idle_in_transaction_time
-------------------+--------------------------------
0.124 | 10505.098
postgres=*# select pg_sleep(10);
postgres=*# select total_active_time, total_idle_in_transaction_time
from pg_stat_activity where pid = pg_backend_pid();
total_active_time | total_idle_in_transaction_time
-------------------+--------------------------------
0.124 | 10505.098
postgres=*# commit;
postgres=# select total_active_time, total_idle_in_transaction_time
from pg_stat_activity where pid = pg_backend_pid();
total_active_time | total_idle_in_transaction_time
-------------------+--------------------------------
10015.796 | 29322.831
[1]
https://www.postgresql.org/docs/14/monitoring-stats.html#MONITORING-STATS-VIEWS
Regards,
Sergey
From b5298301a3f5223bd78c519ddcddbd1bec9cf000 Mon Sep 17 00:00:00 2001
From: Sergey Dudoladov <[email protected]>
Date: Wed, 20 Apr 2022 23:47:37 +0200
Subject: [PATCH] pg_stat_activity: add 'total_active_time' and
'total_idle_in_transaction_time'
catversion bump because of the change in the contents of pg_stat_activity
Author: Sergey Dudoladov, based on the initial version by Rafia Sabih
Reviewed-by: Aleksander Alekseev, Bertrand Drouvot, and Atsushi Torikoshi
Discussion: https://www.postgresql.org/message-id/flat/CA%2BFpmFcJF0vwi-SWW0wYO-c-FbhyawLq4tCpRDCJJ8Bq%3Dja-gA%40mail.gmail.com
---
doc/src/sgml/monitoring.sgml | 20 +++++++++++++
src/backend/catalog/system_views.sql | 4 ++-
src/backend/utils/activity/backend_status.c | 33 ++++++++++++++++-----
src/backend/utils/adt/pgstatfuncs.c | 8 ++++-
src/include/catalog/pg_proc.dat | 6 ++--
src/include/pgstat.h | 10 -------
src/include/utils/backend_status.h | 10 +++++++
src/test/regress/expected/rules.out | 12 ++++----
8 files changed, 75 insertions(+), 28 deletions(-)
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 7dbbab6f5c..943927fe34 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -979,6 +979,26 @@ postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: ser
additional types.
</para></entry>
</row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>total_active_time</structfield> <type>double precision</type>
+ </para>
+ <para>
+ Time in milliseconds this backend spent in <literal>active</literal> and
+ <literal>fastpath function call</literal> states.
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>total_idle_in_transaction_time</structfield> <type>double precision</type>
+ </para>
+ <para>
+ Time in milliseconds this backend spent in <literal>idle in transaction</literal>
+ and <literal>idle in transaction (aborted)</literal> states.
+ </para></entry>
+ </row>
</tbody>
</tgroup>
</table>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index f369b1fc14..2ec6ea2304 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -864,7 +864,9 @@ CREATE VIEW pg_stat_activity AS
s.backend_xmin,
S.query_id,
S.query,
- S.backend_type
+ S.backend_type,
+ S.total_active_time,
+ S.total_idle_in_transaction_time
FROM pg_stat_get_activity(NULL) AS S
LEFT JOIN pg_database AS D ON (S.datid = D.oid)
LEFT JOIN pg_authid AS U ON (S.usesysid = U.oid);
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index c7ed1e6d7a..8fe2929fba 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -336,6 +336,8 @@ pgstat_bestart(void)
lbeentry.st_activity_start_timestamp = 0;
lbeentry.st_state_start_timestamp = 0;
lbeentry.st_xact_start_timestamp = 0;
+ lbeentry.st_total_active_time = 0;
+ lbeentry.st_total_transaction_idle_time = 0;
lbeentry.st_databaseid = MyDatabaseId;
/* We have userid for client-backends, wal-sender and bgworker processes */
@@ -524,6 +526,8 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
TimestampTz start_timestamp;
TimestampTz current_timestamp;
int len = 0;
+ int64 active_time_diff = 0;
+ int64 transaction_idle_time_diff = 0;
TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
@@ -550,6 +554,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
beentry->st_xact_start_timestamp = 0;
beentry->st_query_id = UINT64CONST(0);
proc->wait_event_info = 0;
+
+ beentry->st_total_active_time = 0;
+ beentry->st_total_transaction_idle_time = 0;
PGSTAT_END_WRITE_ACTIVITY(beentry);
}
return;
@@ -575,24 +582,31 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
* If the state has changed from "active" or "idle in transaction",
* calculate the duration.
*/
- if ((beentry->st_state == STATE_RUNNING ||
- beentry->st_state == STATE_FASTPATH ||
- beentry->st_state == STATE_IDLEINTRANSACTION ||
- beentry->st_state == STATE_IDLEINTRANSACTION_ABORTED) &&
+ if ((PGSTAT_IS_ACTIVE(beentry) || PGSTAT_IS_IDLEINTRANSACTION(beentry)) &&
state != beentry->st_state)
{
long secs;
int usecs;
+ int64 usecs_diff;
TimestampDifference(beentry->st_state_start_timestamp,
current_timestamp,
&secs, &usecs);
+ usecs_diff = secs * 1000000 + usecs;
- if (beentry->st_state == STATE_RUNNING ||
- beentry->st_state == STATE_FASTPATH)
- pgstat_count_conn_active_time((PgStat_Counter) secs * 1000000 + usecs);
+ /*
+ * We update per-backend st_total_active_time and st_total_transaction_idle_time
+ * separately from pgStatActiveTime and pgStatTransactionIdleTime
+ * used in pg_stat_database to provide per-DB statistics because
+ * 1. Changing the former values implies modifying beentry and thus
+ * have to be wrapped into PGSTAT_*_WRITE_ACTIVITY macros (see below).
+ * 2. The latter values are reset to 0 once the data has been sent
+ * to the statistics collector.
+ */
+ if (PGSTAT_IS_ACTIVE(beentry))
+ active_time_diff = usecs_diff;
else
- pgstat_count_conn_txn_idle_time((PgStat_Counter) secs * 1000000 + usecs);
+ transaction_idle_time_diff = usecs_diff;
}
/*
@@ -618,6 +632,9 @@ pgstat_report_activity(BackendState state, const char *cmd_str)
beentry->st_activity_start_timestamp = start_timestamp;
}
+ beentry->st_total_active_time += active_time_diff;
+ beentry->st_total_transaction_idle_time += transaction_idle_time_diff;
+
PGSTAT_END_WRITE_ACTIVITY(beentry);
}
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index d9e2a79382..a213211f6a 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -536,7 +536,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
Datum
pg_stat_get_activity(PG_FUNCTION_ARGS)
{
-#define PG_STAT_GET_ACTIVITY_COLS 30
+#define PG_STAT_GET_ACTIVITY_COLS 32
int num_backends = pgstat_fetch_stat_numbackends();
int curr_backend;
int pid = PG_ARGISNULL(0) ? -1 : PG_GETARG_INT32(0);
@@ -856,6 +856,10 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
nulls[29] = true;
else
values[29] = UInt64GetDatum(beentry->st_query_id);
+
+ /* convert to msec */
+ values[30] = Float8GetDatum(beentry->st_total_active_time / 1000.0);
+ values[31] = Float8GetDatum(beentry->st_total_transaction_idle_time / 1000.0);
}
else
{
@@ -884,6 +888,8 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
nulls[27] = true;
nulls[28] = true;
nulls[29] = true;
+ nulls[30] = true;
+ nulls[31] = true;
}
tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 2e41f4d9e8..bcd106897e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5340,9 +5340,9 @@
proname => 'pg_stat_get_activity', prorows => '100', proisstrict => 'f',
proretset => 't', provolatile => 's', proparallel => 'r',
prorettype => 'record', proargtypes => 'int4',
- proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8}',
- proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
- proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id}',
+ proallargtypes => '{int4,oid,int4,oid,text,text,text,text,text,timestamptz,timestamptz,timestamptz,timestamptz,inet,text,int4,xid,xid,text,bool,text,text,int4,text,numeric,text,bool,text,bool,int4,int8,float8,float8}',
+ proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+ proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,leader_pid,query_id,total_active_time,total_idle_in_transaction_time}',
prosrc => 'pg_stat_get_activity' },
{ oid => '3318',
descr => 'statistics: information about progress of backends running maintenance command',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index ac28f813b4..8248e63931 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -469,10 +469,6 @@ extern void pgstat_report_connect(Oid dboid);
(pgStatBlockReadTime += (n))
#define pgstat_count_buffer_write_time(n) \
(pgStatBlockWriteTime += (n))
-#define pgstat_count_conn_active_time(n) \
- (pgStatActiveTime += (n))
-#define pgstat_count_conn_txn_idle_time(n) \
- (pgStatTransactionIdleTime += (n))
extern PgStat_StatDBEntry *pgstat_fetch_stat_dbentry(Oid dbid);
@@ -673,12 +669,6 @@ extern PGDLLIMPORT PgStat_CheckpointerStats PendingCheckpointerStats;
extern PGDLLIMPORT PgStat_Counter pgStatBlockReadTime;
extern PGDLLIMPORT PgStat_Counter pgStatBlockWriteTime;
-/*
- * Updated by pgstat_count_conn_*_time macros, called by
- * pgstat_report_activity().
- */
-extern PGDLLIMPORT PgStat_Counter pgStatActiveTime;
-extern PGDLLIMPORT PgStat_Counter pgStatTransactionIdleTime;
/* updated by the traffic cop and in errfinish() */
extern PGDLLIMPORT SessionEndType pgStatSessionEndCause;
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 7403bca25e..c904714c17 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -168,6 +168,10 @@ typedef struct PgBackendStatus
/* query identifier, optionally computed using post_parse_analyze_hook */
uint64 st_query_id;
+
+ /* time spent in respective states in usec */
+ int64 st_total_active_time;
+ int64 st_total_transaction_idle_time;
} PgBackendStatus;
@@ -231,6 +235,12 @@ typedef struct PgBackendStatus
((before_changecount) == (after_changecount) && \
((before_changecount) & 1) == 0)
+/* Macros to identify the states for time accounting */
+#define PGSTAT_IS_ACTIVE(s) \
+ ((s)->st_state == STATE_RUNNING || (s)->st_state == STATE_FASTPATH)
+#define PGSTAT_IS_IDLEINTRANSACTION(s) \
+ ((s)->st_state == STATE_IDLEINTRANSACTION || \
+ (s)->st_state == STATE_IDLEINTRANSACTION_ABORTED)
/* ----------
* LocalPgBackendStatus
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 7ec3d2688f..4c9f5f8369 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1758,8 +1758,10 @@ pg_stat_activity| SELECT s.datid,
s.backend_xmin,
s.query_id,
s.query,
- s.backend_type
- FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+ s.backend_type,
+ s.total_active_time,
+ s.total_idle_in_transaction_time
+ FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
LEFT JOIN pg_database d ON ((s.datid = d.oid)))
LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
pg_stat_all_indexes| SELECT c.oid AS relid,
@@ -1871,7 +1873,7 @@ pg_stat_gssapi| SELECT s.pid,
s.gss_auth AS gss_authenticated,
s.gss_princ AS principal,
s.gss_enc AS encrypted
- FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+ FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
WHERE (s.client_port IS NOT NULL);
pg_stat_progress_analyze| SELECT s.pid,
s.datid,
@@ -2052,7 +2054,7 @@ pg_stat_replication| SELECT s.pid,
w.sync_priority,
w.sync_state,
w.reply_time
- FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+ FROM ((pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
JOIN pg_stat_get_wal_senders() w(pid, state, sent_lsn, write_lsn, flush_lsn, replay_lsn, write_lag, flush_lag, replay_lag, sync_priority, sync_state, reply_time) ON ((s.pid = w.pid)))
LEFT JOIN pg_authid u ON ((s.usesysid = u.oid)));
pg_stat_replication_slots| SELECT s.slot_name,
@@ -2086,7 +2088,7 @@ pg_stat_ssl| SELECT s.pid,
s.ssl_client_dn AS client_dn,
s.ssl_client_serial AS client_serial,
s.ssl_issuer_dn AS issuer_dn
- FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id)
+ FROM pg_stat_get_activity(NULL::integer) s(datid, pid, usesysid, application_name, state, query, wait_event_type, wait_event, xact_start, query_start, backend_start, state_change, client_addr, client_hostname, client_port, backend_xid, backend_xmin, backend_type, ssl, sslversion, sslcipher, sslbits, ssl_client_dn, ssl_client_serial, ssl_issuer_dn, gss_auth, gss_princ, gss_enc, leader_pid, query_id, total_active_time, total_idle_in_transaction_time)
WHERE (s.client_port IS NOT NULL);
pg_stat_subscription| SELECT su.oid AS subid,
su.subname,
--
2.32.0
