Обсуждение: Problems monitoring DB activity
Hello, When I do the following: SELECT * FROM pg_catalog.pg_stat_activity; The current_query and query_start columns are always empty. Obviously this makes it hard to monitor problems with the various admin tools, etc. I'm guessing there's a setting or something that needs updated, I just need a point in the right direction. DB is 7.4.2 Thanks
On Fri, Oct 08, 2004 at 09:54:08AM -0400, Doug Y wrote: > > SELECT * FROM pg_catalog.pg_stat_activity; > > The current_query and query_start columns are always empty. Obviously > this makes it hard to monitor problems with the various admin tools, etc. Does postgresql.conf have stats_command_string = true? -- Michael Fuhr http://www.fuhr.org/~mfuhr/
Michael Fuhr wrote: >On Fri, Oct 08, 2004 at 09:54:08AM -0400, Doug Y wrote: > > >>SELECT * FROM pg_catalog.pg_stat_activity; >> >>The current_query and query_start columns are always empty. Obviously >>this makes it hard to monitor problems with the various admin tools, etc. >> >> > >Does postgresql.conf have stats_command_string = true? > Thanks, setting that did the trick.... whats the performance hit for having it enabled?
On Fri, Oct 08, 2004 at 10:46:56AM -0400, Doug Y wrote: > Michael Fuhr wrote: > > > >Does postgresql.conf have stats_command_string = true? > > > Thanks, setting that did the trick.... whats the performance hit for > having it enabled? I haven't done any tests to determine the performance penalty; maybe one of the developers or somebody who's done some benchmarks can comment. The "Annotated postgresql.conf and Global User Configuration (GUC) Guide"[1] says that "Enabling statistics collection costs a small amount of time per query, but is invaluable for debugging and performance tuning." [1] http://www.varlena.com/varlena/GeneralBits/Tidbits/annotated_conf_e.html -- Michael Fuhr http://www.fuhr.org/~mfuhr/
Sounds like the Oracle parameter TIMED_STATISTICS. Costs you soo little in performance, but saves you a pile in troubleshooting. Many DBA's still set it to false to "save the expense". Nice to know the same exists here. Dick Goulet Senior Oracle DBA Oracle Certified 8i DBA -----Original Message----- From: Michael Fuhr [mailto:mike@fuhr.org] Sent: Friday, October 08, 2004 11:15 AM To: Doug Y Cc: pgsql-admin@postgresql.org Subject: Re: [ADMIN] Problems monitoring DB activity On Fri, Oct 08, 2004 at 10:46:56AM -0400, Doug Y wrote: > Michael Fuhr wrote: > > > >Does postgresql.conf have stats_command_string = true? > > > Thanks, setting that did the trick.... whats the performance hit for > having it enabled? I haven't done any tests to determine the performance penalty; maybe one of the developers or somebody who's done some benchmarks can comment. The "Annotated postgresql.conf and Global User Configuration (GUC) Guide"[1] says that "Enabling statistics collection costs a small amount of time per query, but is invaluable for debugging and performance tuning." [1] http://www.varlena.com/varlena/GeneralBits/Tidbits/annotated_conf_e.html -- Michael Fuhr http://www.fuhr.org/~mfuhr/ ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html