Re: [Testperf-general] Re: First set of OSDL Shared Memscalability results, some wierdness ...

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Wong <markw@osdl.org>
Cc: josh@agliodbs.com, Simon Riggs <simon@2ndquadrant.com>, testperf-general@pgfoundry.org, pgsql-performance@postgresql.org
Date: 2004-10-15T21:44:34Z
Lists: pgsql-hackers, pgsql-performance
Mark Wong <markw@osdl.org> writes:
> On Fri, Oct 15, 2004 at 05:27:29PM -0400, Tom Lane wrote:
>> Hmm, in that case the cost deserves some further investigation.  Can we
>> find out just what that routine does and where it's being called from?

> There's a call-graph feature with oprofile as of version 0.8 with
> the opstack tool, but I'm having a terrible time figuring out why the
> output isn't doing the graphing part.  Otherwise, I'd have that
> available already...

I was wondering if this might be associated with do_sigaction.
do_sigaction is only 0.23 percent of the runtime according to the
oprofile results:
http://khack.osdl.org/stp/298124/oprofile/DBT_2_Profile-all.oprofile.txt
but the profile results for the same run:
http://khack.osdl.org/stp/298124/profile/DBT_2_Profile-tick.sort
show do_sigaction very high and recalc_sigpending_tsk nowhere at all.
Something funny there.

			regards, tom lane