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Message-ID: <4451D95E.9080308@logix-tt.com>
Date: Fri, 28 Apr 2006 10:59:10 +0200
From: Markus Schaber <schabi@logix-tt.com>
Organization: Logical Tracking and Tracing International AG, Switzerland
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To: pgsql-performance@postgresql.org
Cc: guoping.zhang@nec.com.au
Subject: Re: how unsafe (or worst scenarios) when setting fsync
References: <004101c66a7e$4ab95000$74304c93@eddy>
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Hk, Guoping,

Guoping Zhang wrote:

> a) The tests consists of ten thousands very small transactions, which are
> not grouped, that is why so slow with compare to set fsync off.

If those transactions are submitted by concurrent applications over
several simulataneous connections, playing with commit_delay and
commit_siblins may improve your situation.

HTH,
Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org