From: Tom Lane <tgl@sss.pgh.pa.us>
To: Craig Ringer <craig@postnewspapers.com.au>
Cc: Eliot Gable <egable+pgsql-performance@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Highly Efficient Custom Sorting
Date: Fri, 02 Jul 2010 00:08:50 -0400
Message-ID: <4767.1278043730@sss.pgh.pa.us> (raw)
In-Reply-To: <4C2D574E.5030308@postnewspapers.com.au>
References: <AANLkTikrA8M3cncIHkFqsJ78TzCnQdriE0GjvK8XjB9E@mail.gmail.com>
<4C2D574E.5030308@postnewspapers.com.au>
Craig Ringer <craig@postnewspapers.com.au> writes:
> On 02/07/10 08:46, Eliot Gable wrote:
>> So, the bottom line is, I need a faster way to do this sorting.
> You haven't showed us how you're doing it at the moment, so it's awfully
> hard to comment usefully on possible approaches.
I'm guessing from tea leaves, but the impression I got from Eliot's
description is that he's using plpgsql functions as sort comparators.
It's not surprising that that sucks performance-wise compared to having
the equivalent logic in C/C++ functions used as comparators on the
client side. plpgsql is no speed demon. Best fix might be to code the
comparators as C functions on the server side.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, craig@postnewspapers.com.au, egable+pgsql-performance@gmail.com
Subject: Re: Highly Efficient Custom Sorting
In-Reply-To: <4767.1278043730@sss.pgh.pa.us>
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