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To: Laszlo Nagy <gandalf@designaproduct.biz>
Cc: pgsql-performance@postgresql.org
Subject: Re: Poor performance on seq scan
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From: Guillaume Cottenceau <gc@mnc.ch>
Date: 12 Sep 2006 14:36:22 +0200
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Laszlo Nagy <gandalf 'at' designaproduct.biz> writes:

> This is a mirrored disk with two SATA disks. In theory, writing should
> be slower than reading. Is this a hardware problem? Or is it that
> "sync" did not do the sync?

SATA disks are supposed to be capable of lying to pg's fsync (pg
asking the kernel to synchronize a write and waiting until it is
finished). Same can probably happen to the "sync" command.

-- 
Guillaume Cottenceau
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