From: Tom Lane <tgl@sss.pgh.pa.us>
To: Achilleus Mantzios <achill@matrix.gatewaynet.com>
Cc: pgsql-general@postgresql.org
Cc: pgsql-sql@postgresql.org
Subject: Re: FreeBSD, Linux: select, select count(*) performance
Date: Wed, 27 Nov 2002 11:56:34 -0500
Message-ID: <18354.1038416194@sss.pgh.pa.us> (raw)
In-Reply-To: <Pine.LNX.4.44.0211271826120.27228-100000@matrix.gatewaynet.com>
References: <Pine.LNX.4.44.0211271826120.27228-100000@matrix.gatewaynet.com>
Achilleus Mantzios <achill@matrix.gatewaynet.com> writes:
> On Wed, 27 Nov 2002, Tom Lane wrote:
>> You didn't say what was *in* the table, exactly ... but I'm betting
>> there are a lot of toasted columns, and that the extra runtime
>> represents the time to fetch (and perhaps decompress) the TOAST entries.
> 278 columns of various types.
> namely,
> [snip]
Hmm, no particularly wide columns there --- but 278 columns is a lot.
I think the extra time might just be the time involved in fetching all
those column values out of the table row?
If you're interested in pursuing it, I'd suggest rebuilding the backend
with profiling enabled so you can see exactly where the time goes.
regards, tom lane
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, achill@matrix.gatewaynet.com, pgsql-general@postgresql.org
Subject: Re: FreeBSD, Linux: select, select count(*) performance
In-Reply-To: <18354.1038416194@sss.pgh.pa.us>
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