Thread: About pg_stat_activity

Hi, im César, im developing an app that saves information included in "pg_stat_activity" view in order to monitor querys. The objective of this app is to gather information about querys that take to long to finish and overload the server. I was wandering if I could see somehwere the implementation of "pg_stat_activity" view, in order to not save the information in another table, I need to use historical information about querys.
If you could help looking about this, or if you know about an app that already do this, please let me know.

On Wednesday 02 February 2011 16:21:47 Cesar Arrieta wrote:

Hi,

> If you could help looking about this, or if you know about an app that
> already do this, please let me know.

have a look for http://pgfouine.projects.postgresql.org/
and http://pgfoundry.org/projects/pgstatspack/

HTH,
Jens

>I was wandering if I could see somehwere the implementation of "pg_stat_activity" view

From psql

\d+ pg_stat_activity
---
Maciek Sakrejda | System Architect | Truviso

1065 E. Hillsdale Blvd., Suite 215
Foster City, CA 94404
www.truviso.com

Cesar Arrieta wrote:
> im developing an app that saves information included in
> "pg_stat_activity" view in order to monitor querys. The objective of
> this app is to gather information about querys that take to long to
> finish and overload the server.

I hope you're already setting log_min_duration_statement, then analyzing
the resulting logs using something like pgFouine.  If you have
PostgreSQL 8.4 or later, possibly add loading the auto_explain module as
well, or collecting the data using pg_stat_statements instead can be
useful.  Trying to grab this info in real-time from pg_stat_activity
instead is a lot of work and won't give you results as good.  If you're
already doing something like that and are just looking to increase the
amount of info you collect by also looking at pg_stat_activity, that can
be worthwhile.

Maciek just gave the quickest answer to your main question; I'll just
add that reading the source code to the file system_views.sql will show
you how pg_stat_activity as well as other interesting built-in views work.

--
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
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