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From: Jakub Ouhrabka <kuba@comgate.cz>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Linux/PostgreSQL scalability issue - problem with 8 cores
Date: Tue, 15 Jan 2008 16:45:57 +0100
Message-ID: <478CD535.6030004@comgate.cz> (raw)
In-Reply-To: <23470.1200410459@sss.pgh.pa.us>
References: <flii57$748$1@news.hub.org>
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	<23470.1200410459@sss.pgh.pa.us>

 > Huh.  One transaction truncating a dozen tables?  That would match the
 > sinval trace all right ...

It should be 4 tables - the shown log looks like there were more truncates?

 > You might be throwing the baby out with the bathwater,
 > performance-wise.

Yes, performance was the initial reason to use truncate instead of 
delete many years ago. But today the truncated tables usualy contain 
exactly one row - quick measurements now show that it's faster to issue 
delete instead of truncate in this case.

Again, many thanks for your invaluable advice!

Kuba



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