Re: optimizing Postgres queries

From: Rod Taylor <pg(at)rbt(dot)ca>
To: David Teran <david(dot)teran(at)cluster9(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Postgresql Performance <pgsql-performance(at)postgresql(dot)org>
Subject: Re: optimizing Postgres queries
Date: 2004-01-09 03:16:49
Message-ID: 1073618208.322.18.camel@jester
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On Mon, 2004-01-05 at 14:57, David Teran wrote:
> ... wow:
>
> executing a batch file with about 4250 selects, including lots of joins
> other things PostgreSQL 7.4 is about 2 times faster than FrontBase
> 3.6.27. OK, we will start to make larger tests but this is quite
> interesting already: we did not optimize a lot, just invoked VACUUM
> ANALYZE and then the selects ;-)
>
> Thanks to all who answered to this thread.

I presume that batch file was executed linearly -- no parallelism?
You're actually testing one of PostgreSQL's shortcomings.

PostgreSQL (in my experience) does much better in such comparisons with
a parallel load -- multiple connections executing varied work (short
selects, complex selects, inserts, updates, deletes).

Anyway, just a tip that you will want to test your actual load. If you
do batch work with a single thread, what you have is fine. But if you
have a website with tens or hundreds of simultaneous connections then
your non-parallel testing will not reflect that work load.

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