From: Markus Schaber <schabi@logix-tt.com>
To: Francisco Reyes <lists@stringsutils.com>
Cc: Pgsql performance <pgsql-performance@postgresql.org>
Subject: Re: Inserts optimization?
Date: Tue, 18 Apr 2006 11:02:34 +0200
Message-ID: <4444AB2A.5080607@logix-tt.com> (raw)
In-Reply-To: <cone.1145031012.290269.26335.1000@zoraida.natserv.net>
References: <cone.1144953939.190214.95544.5001@35st-server.simplicato.com>
<200604141400.38982.mcousin@sigma.fr>
<cone.1145031012.290269.26335.1000@zoraida.natserv.net>
Hi, Francisco,
Francisco Reyes wrote:
> I only wonder what is safer.. using a second or two in commit_delay or
> using fsync = off.. Anyone cares to comment?
It might be that you misunderstood commit_delay. It will not only delay
the disk write, but also block your connnection until the write actually
is performed.
It will rise the throughput in multi-client scenarios, but will also
rise the latency, and it will absolutely bring no speedup in
single-client scenarios.
It does not decrease safety (in opposite to fsync=off), data will be
consistent, and any application that has successfully finished a commit
can be shure their data is on the platters.[1]
HTH,
Markus
[1] As long as the platters don't lie, but that's another subject.
--
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf. | Software Development GIS
Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org
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To: pgsql-performance@postgresql.org
Cc: schabi@logix-tt.com, lists@stringsutils.com
Subject: Re: Inserts optimization?
In-Reply-To: <4444AB2A.5080607@logix-tt.com>
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