Re: [Testperf-general] Re: First set of OSDL Shared Memscalability results, some wierdness ...
Mark Wong <markw@osdl.org>
From: Mark Wong <markw@osdl.org>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: josh@agliodbs.com, Simon Riggs <simon@2ndquadrant.com>, testperf-general@pgfoundry.org, pgsql-performance@postgresql.org
Date: 2004-10-15T21:32:06Z
Lists: pgsql-hackers, pgsql-performance
On Fri, Oct 15, 2004 at 05:27:29PM -0400, Tom Lane wrote: > Josh Berkus <josh@agliodbs.com> writes: > >> I suspect the reason recalc_sigpending_tsk is so high is that the > >> original coding of PG_TRY involved saving and restoring the signal mask, > >> which led to a whole lot of sigsetmask-type kernel calls. Is this test > >> with beta3, or something older? > > > Beta3, *without* Gavin or Neil's Futex patch. > > 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... Mark