Re: Overhead for stats_command_string et al, take 2 - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Overhead for stats_command_string et al, take 2
Date
Msg-id 200606261852.k5QIqop14441@momjian.us
Whole thread Raw
In response to Overhead for stats_command_string et al, take 2  (Greg Stark <gsstark@mit.edu>)
List pgsql-hackers
Tom Lane wrote:
> I wrote:
> > IIRC, newer BSDen use a kernel call for this, so you should be able to
> > measure it on your own machine.  Just tweak ps_status.c to force it to
> > select PS_USE_NONE instead of PS_USE_SETPROCTITLE to generate a
> > comparison case.  I'll try it on my old HPUX box too.
> 
> On HPUX, I get a median time of 5.59 sec for CVS HEAD vs 5.36 sec with
> ps_status diked out, for the test case of 10000 "SELECT 1;" as separate
> transactions, assert-disabled build.  So, almost 10% overhead.  Given
> that the transactions can't get any more trivial than this, that's about
> a worst-case number.  Not sure if it's worth worrying about or not.
> However Kris Kennaway's report a couple weeks ago suggested things might
> be worse on BSD.

Yep, I see 8% here.  I will add a patch to allow the ps display to be
turned off.

--  Bruce Momjian   bruce@momjian.us EnterpriseDB    http://www.enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


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