Re: [RFC] Change the default of update_process_title to off

On Tue, Aug 16, 2016 at 11:53:25AM +0200, Magnus Hagander wrote:
> On Fri, Aug 5, 2016 at 12:25 PM, Tsunakawa, Takayuki <
> tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com> wrote:
>
> > From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]
> > Yeah, I think I agree.  It would be bad to disable it by default on Unix,
> > because ps(1) is a very standard tool there, but the same argument
> doesn't
> > hold for Windows.
>
> It seems that we could reach a consensus.  The patch is attached.  I'll add
> this to the next CommitFest.
>
> > Another route to a solution would be to find a cheaper way to update the
> > process title on Windows ... has anyone looked for alternatives?
>
> I couldn't find an alternative solution after asking some Windows support
> staff.
>
>
> FWIW, I remember this from back in the days when this was written. We kind of
> expected this would be slow already back then, but couldn't find a better way
> at the time either. And back then, I guess there were just enough *other*
> things that were slow with pg-on-windows that it didn't become as obvious.
>
> So - +1 for changing the defaults as suggested.

I am shocked at how much a speedup we get by turning off the process
title on Windows:

> From Tsunakawa, Takayuki
>
> C:\> pgbench -h <db_server> -T 30 -c #clients -j 12 -S benchdb
>
> [Windows]
> #clients on off
> 12 29793 38169
> 24 31587 87237
> 48 32588 83335
> 96 34261 67668

This ranges from a 28% to a 97% speed improvement on Windows! Those are
not typos! This is a game-changer for use of Postgres on Windows for
certain workloads!

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

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