From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@enterprisedb.com>
cc: Andres Freund <andres@anarazel.de>,
        pgsql-committers <pgsql-committers@postgresql.org>
Subject: Re: pgsql: Add parallel-aware hash joins.
In-reply-to: <21339.1516633310@sss.pgh.pa.us>
References: <E1eRwXy-0004IK-TO@gemulon.postgresql.org>
 <20171221092940.gbxcszbzsr5khsfr@alap3.anarazel.de>
 <20171221095550.d3e7xhoakcowhu5b@alap3.anarazel.de>
 <CAEepm=3eS6ra8oBCYsYYjPNsPqb2R_TaGQK8SGRFq_7gbP8RUg@mail.gmail.com>
 <CAEepm=0WxwzpHVHt3PcWHBV=L3k3FDb6dvMq1A2Li49LGBa7TA@mail.gmail.com>
 <20171222082203.fl6rpzlqnm4h7h6h@alap3.anarazel.de>
 <CAEepm=04WhyY65BpE2g_8E==ayhBXjV9JbyR-+9N4McmY3SQkQ@mail.gmail.com>
 <30219.1514428346@sss.pgh.pa.us>
 <CAEepm=1OyZcCAxAEWYhmeg0qmWyYF2O2yW7s7A4uVTt-dgRRyQ@mail.gmail.com>
 <4503.1514435195@sss.pgh.pa.us>
 <CAEepm=2rZ6NzdR7Rk5jsXsJR8M_kRmi+0JSY1x6DLSdmBb-=VA@mail.gmail.com>
 <CAEepm=1KTKEKW3KBbZwN6Ohh+rhuXjxC_f-F4VHR8Y6UWC=xVQ@mail.gmail.com>
 <21339.1516633310@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Mon, 22 Jan 2018 10:01:50 -0500"
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Date: Mon, 22 Jan 2018 18:53:10 -0500
Message-ID: <24384.1516665190@sss.pgh.pa.us>
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I wrote:
> Anyway, it looks like we should write off these longfin timings as
> ambient noise :-(

Here's a possibly more useful graph of regression test timings over
the last year.  I pulled this from the buildfarm database: it is the
reported runtime for the "installcheck-C" step in each successful
build of HEAD on dromedary, going back to Jan. 2017.  I picked dromedary
because I know that that machine hasn't gotten any software updates
nor is there anything else very interesting going on on it.  I dropped
three or four obvious outlier reports (possibly those ran during the
machine's nightly backup cron job).  The reported runtime is only
precise to 1s, and a couple seconds jitter is hardly surprising, so
there's a good deal of noise.  Still, it's possible to discern when
I put some effort into test runtime reduction back in April, and
it can be seen that things have gotten notably slower since the
beginning of November.

			regards, tom lane


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