From: Neil Conway <neilc@samurai.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Gary Doades <gpd@gpdnet.co.uk>
Cc: pgsql-performance@postgresql.org
Cc: pgsql-hackers@postgresql.org
Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index
Date: Wed, 15 Feb 2006 21:12:52 -0500
Message-ID: <1140055972.31672.42.camel@localhost.localdomain> (raw)
In-Reply-To: <20781.1140046109@sss.pgh.pa.us>
References: <43F38867.6010701@gpdnet.co.uk>
<19510.1140036968@sss.pgh.pa.us>
<19779.1140038874@sss.pgh.pa.us>
<43F39E53.1020009@gpdnet.co.uk>
<20781.1140046109@sss.pgh.pa.us>
On Wed, 2006-02-15 at 18:28 -0500, Tom Lane wrote:
> It seems clear that our qsort.c is doing a pretty awful job of picking
> qsort pivots, while glibc is mostly managing not to make that mistake.
> I haven't looked at the glibc code yet to see what they are doing
> differently.
glibc qsort is actually merge sort, so I'm not surprised it avoids this
problem.
-Neil
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To: pgsql-performance@postgresql.org
Cc: neilc@samurai.com, tgl@sss.pgh.pa.us, gpd@gpdnet.co.uk, pgsql-hackers@postgresql.org
Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index
In-Reply-To: <1140055972.31672.42.camel@localhost.localdomain>
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