Re: COMMIT takes long time for read only transaction

Mario Splivalo <mario.splivalo@megafon.hr> wrote:

> 2011-05-26 18:25:51.624 CEST [16163] <ample@knjiz>
> [192.168.1.5(32431)]
> COMMIT LOG:  duration: 11159.202 ms  statement: COMMIT
> 2011-05-26 18:26:05.788 CEST [16163] <ample@knjiz>
> [192.168.1.5(32431)]
> COMMIT LOG:  duration: 326.856 ms  statement: COMMIT
>
> This is a grep from a postgres log when I had logging of all
> statements enabled. I did grep by the local pid (16163), and what
> I don't understand is:
> - why is first COMMIT taking 11 seconds, when there are only
> SELECTs in the transaction? SELECTS don't call any user defined
> functions, just plain reads from the tables.
> - what is that second COMMIT? If I issue COMMIT without 'BEGIN'
> shouldn't I get: "COMMIT WARNING:  there is no transaction in
> progress"

Hard to say what's going on without knowing more about your logging
configuration.  If you run this query and post the results it will
help clarify the situation:

http://wiki.postgresql.org/wiki/Server_Configuration

-Kevin