From: Yura Sokolov <funny.falcon@gmail.com>
To: Stephen Frost <sfrost@snowman.net>
Cc: Michael Paquier <michael.paquier@gmail.com>
Cc: Peter Geoghegan <pg@bowt.ie>
Cc: Andres Freund <andres@anarazel.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Claudio Freire <klaussfreire@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>
Cc: Sokolov Yura <funny.falcon@postgrespro.ru>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>
Cc: PostgreSQL-Dev <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] Small improvement to compactify_tuples
Date: Sun, 25 Feb 2018 21:39:46 +0300
Message-ID: <9410de56-794b-147f-20f2-d5ef28e98e45@gmail.com> (raw)
In-Reply-To: <20180123033429.GF2416@tamriel.snowman.net>
References: <CAGTBQpZgs4hVmDtHg4F6MDJuAE9-U=z6d+yJzjPsZup7AZhV0Q@mail.gmail.com>
<22996.1510160560@sss.pgh.pa.us>
<CAL-rCA3n4Neat4pH382nuZ9v0-SCZOBJ=KHT5CoBGXim=KTAhw@mail.gmail.com>
<CAL-rCA2cCyvapkb15fADR3qKsRMo+XimPgmGviur1ui-y0q-aQ@mail.gmail.com>
<CAH2-WznEQBxeij1_PnczUD=vQqS0aPWOxJAkmjH_rXoBpeo0ZQ@mail.gmail.com>
<CAL-rCA3=MiVU7SWenhPL0a3e5KfOkzvXZDp_WL+ea2Ky57Fqdg@mail.gmail.com>
<20171128224150.syswowiaiojth7ke@alap3.anarazel.de>
<CAH2-Wzk19G5=RxQpgfUirRvihjrMvZSMSi=u53TbMbvLj1+5vA@mail.gmail.com>
<CAB7nPqS4JRP_xyO3YCuBktGhTkDMRvg3-WBTgLqwpnLrtx-Qzg@mail.gmail.com>
<CAL-rCA2n7UfVu1Ui0f+7cVN4vAKVM0+-cZKb_ka6-mGQBAF92w@mail.gmail.com>
<20180123033429.GF2416@tamriel.snowman.net>
23.01.2018 06:34, Stephen Frost пишет:
> Greetings,
>
> * Юрий Соколов (funny.falcon@gmail.com) wrote:
>> On Wed, Nov 29, 2017 at 8:00 AM, Peter Geoghegan <pg@bowt.ie> wrote:
>>> On Tue, Nov 28, 2017 at 2:41 PM, Andres Freund <andres@anarazel.de> wrote:
>>>> Maybe it's a stupid question. But would we still want to have this after
>>>> the change? These should be just specializations of the template version
>>>> imo.
>>
>> "generic" version operates on bytes, and it will be a bit hard to combine
>> it with
>> templated version. Not impossible, but it will look ugly.
>
> If that's the case then does it really make sense to make this change..?
I don't think it is really necessary to implement generic version
through templated. It is much better to replace generic version with
templated in places where it matters for performance.
>
>> In attach fixed qsort_template version.
>> And version for compactify_tuples with bucket_sort and templated qsort.
>
> While having the patch is handy, I'm not seeing any performance numbers
> on this version, and I imagine others watching this thread are also
> wondering about things like a test run that just uses the specialized
> qsort_itemIds() without the bucketsort.
>
> Are you planning to post some updated numbers and/or an updated test
> case that hopefully shows best/worst case with this change? Would be
> good to get that on a couple of platforms too, if possible, since we've
> seen that the original benchmarks weren't able to be consistently
> repeated across different platforms. Without someone doing that
> leg-work, this doesn't seem like it'll be moving forward.
Updated numbers are (same benchmark on same notebook, but with new
master, new ubuntu and later patch version) (average among 6 runs):
master - 16135tps
with templated qsort - 16199tps
with bucket sort - 16956tps
Difference is still measurable, but less significant. I don't know why.
Rebased version of first patch (qsorted tamplate) is in atttach.
With regards,
Sokolov Yura.
Attachments:
[application/gzip] 0001-Header-for-customized-qsort.patch.gz (6.2K, ../9410de56-794b-147f-20f2-d5ef28e98e45@gmail.com/2-0001-Header-for-customized-qsort.patch.gz)
download
[application/pgp-signature] signature.asc (454B, ../9410de56-794b-147f-20f2-d5ef28e98e45@gmail.com/3-signature.asc)
download
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-hackers@postgresql.org
Cc: funny.falcon@gmail.com, sfrost@snowman.net, michael.paquier@gmail.com, pg@bowt.ie, andres@anarazel.de, tgl@sss.pgh.pa.us, klaussfreire@gmail.com, robertmhaas@gmail.com, funny.falcon@postgrespro.ru, alvherre@2ndquadrant.com, hlinnaka@iki.fi
Subject: Re: [HACKERS] Small improvement to compactify_tuples
In-Reply-To: <9410de56-794b-147f-20f2-d5ef28e98e45@gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox