2026-03-12 21:01:38

tiddlywiki/PostgreSQL - pgSentinel.tid

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+created: 20190616221128760
+creator: vplesnila
+modified: 20190616221559458
+modifier: vplesnila
+tags: PostgreSQL
+title: PostgreSQL - pgSentinel
+type: text/vnd.tiddlywiki
+
+! Parameteres for pg_stat_statements
+```
+shared_preload_libraries = 'pg_stat_statements'
+
+pg_stat_statements.max = 10000
+pg_stat_statements.track = all
+```
+
+! Parameteres for pg_sentinel
+```
+shared_preload_libraries = 'pg_stat_statements,pgsentinel'
+# Icncrease the max size of the query strings Postgres records
+track_activity_query_size = 2048
+# Track statements generated by stored procedures as well
+pg_stat_statements.track = all
+```
+
+! Create the extensions at the DATABASE level
+
+```
+create extension pg_stat_statements;
+create extension pgsentinel;
+```
+
+! Performance views
+* `pg_stat_activity`
+* `pg_stat_statements`
+* `pg_active_session_history` (history of `pg_stat_activity`)
+
+! Examples
+
+```
+select ash_time,top_level_query,query,queryid,wait_event_type,wait_event from pg_active_session_history where query != 'ROLLBACK' order by ash_time desc limit 15;
+
+select ash_time, wait_event, wait_event_type from pg_active_session_history where queryid=3548524963606505593 order by ash_time desc limit 15; 
+```