Re: pg 8.1.3, AIX, huge box, painfully slow. - Mailing list pgsql-performance

From Tom Lane
Subject Re: pg 8.1.3, AIX, huge box, painfully slow.
Date
Msg-id 17055.1144447009@sss.pgh.pa.us
Whole thread Raw
In response to Re: pg 8.1.3, AIX, huge box, painfully slow.  (Gavin Hamill <gdh@laterooms.com>)
Responses Re: pg 8.1.3, AIX, huge box, painfully slow.
List pgsql-performance
Gavin Hamill <gdh@laterooms.com> writes:
> There's truss installed which seems to do the same as strace on
> Linux... and here's a wildly non-scientific  glance..  I watched the
> 'topas' output (top for AIX) , identified a PID that was doing a lot of
> work, then attached truss to that pid. In addition to lots of send
> (), recv() and lseek()s...

Those are good, they represent real work getting done.

> about once a minute I saw hundreds of calls
> to __semop() interspersed with _select(),

This is not good.  Did the semop storms coincide with visible slowdown?
(I'd assume so, but you didn't actually say...)

            regards, tom lane

pgsql-performance by date:

Previous
From: "Luke Lonergan"
Date:
Subject: Re: pg 8.1.3, AIX, huge box, painfully slow.
Next
From: Tom Lane
Date:
Subject: Re: pg 8.1.3, AIX, huge box, painfully slow.