pg_stat_activit y versus ps

[Jeff Amiel]

I ran a home-grown self continuous stress test tool against my 7.4.2
database.

I banged 'ps' (running freebsd) while it was active and witnessed
several of the 'back end' postgres processes exeucting queries, commits,
inserts, etc....(the actual work the processes were doing was listed in
the 'ps' output)
however, if I checked pg_stat_activit y during the same time period, I
saw nothing populated in the current_query column...ever.

Am I misunderstandin g what the pg_stat_activit y table is for? I
confirmed that the procpid listed in pg_stat_activit y was the same as
listed in my 'ps' process list....
Jeff

---------------------------(end of broadcast)---------------------------
TIP 3: if posting/reading through Usenet, please send an appropriate
subscribe-nomail command to ma*******@postg resql.org so that your
message can get through to the mailing list cleanly

[Tom Lane]

Jeff Amiel <ja****@istream imaging.com> writes:

however, if I checked pg_stat_activit y during the same time period, I
saw nothing populated in the current_query column...ever.

Did you have it turned on? (stats_command_ string config parameter)

Were you checking as superuser?

regards, tom lane

---------------------------(end of broadcast)---------------------------
TIP 4: Don't 'kill -9' the postmaster

[Jeff Amiel]

That was it. (not having it turned on. duh).
Guess I should have read section 23.2 of the docs..."The Statistics
Collector"
Thanks for the heads up.

Jeff
Tom Lane wrote:

Jeff Amiel <ja****@istream imaging.com> writes:

however, if I checked pg_stat_activit y during the same time period, I
saw nothing populated in the current_query column...ever.

Did you have it turned on? (stats_command_ string config parameter)

Were you checking as superuser?

regards, tom lane

---------------------------(end of broadcast)---------------------------
TIP 8: explain analyze is your friend

[Bruce Momjian]

Jeff Amiel wrote:

That was it. (not having it turned on. duh).
Guess I should have read section 23.2 of the docs..."The Statistics
Collector"

8.0 will give clear output showing it is not turned on our you don't
have permissions.

--
Bruce Momjian | http://candle.pha.pa.us
pg***@candle.ph a.pa.us | [phone]
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

---------------------------(end of broadcast)---------------------------
TIP 8: explain analyze is your friend