From: Stephen Frost <sfrost@snowman.net>
To: Merlin Moncure <mmoncure@gmail.com>
Cc: Pg Performance list <pgsql-performance@postgresql.org>
Subject: Re: odd variances in count(*) times
Date: Mon, 9 Oct 2006 14:30:26 -0400
Message-ID: <20061009183026.GT24675@kenobi.snowman.net> (raw)
In-Reply-To: <b42b73150610091117n29e8d9d5yed07abe8a228593e@mail.gmail.com>
References: <b42b73150610091117n29e8d9d5yed07abe8a228593e@mail.gmail.com>
* Merlin Moncure (mmoncure@gmail.com) wrote:
> explain analyze select 5000!;
> A: 2.4 seconds
> B: 1.8 seconds
>
> explain analyze select count(*) from generate_series(1,500000);
> A: 0.85 seconds
> B: 4.94 seconds
Try w/o the explain analyze. It adds quite a bit of overhead and that
might be inconsistant between the systems (mainly it may have to do with
the gettimeofday() calls being implemented differently between Windows
and Linux..).
Thanks,
Stephen
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To: pgsql-performance@postgresql.org
Cc: sfrost@snowman.net, mmoncure@gmail.com
Subject: Re: odd variances in count(*) times
In-Reply-To: <20061009183026.GT24675@kenobi.snowman.net>
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