Re: Overhead for stats_command_string et al, take 2

[Bruce Momjian <bruce(at)momjian(dot)us>]

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.

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  Bruce Momjian   bruce(at)momjian(dot)us
  EnterpriseDB    http://www.enterprisedb.com

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