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To: mark@mark.mielke.cc
cc: "Jim C. Nasby" <jnasby@pervasive.com>, Steve Poe <steve.poe@gmail.com>,
	pgsql-performance@postgresql.org
Subject: Re: Postgresql Performance on an HP DL385 and 
In-reply-to: <20060815202948.GC13695@mark.mielke.cc> 
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Comments: In-reply-to mark@mark.mielke.cc
	message dated "Tue, 15 Aug 2006 16:29:48 -0400"
Date: Tue, 15 Aug 2006 16:40:09 -0400
Message-ID: <20113.1155674409@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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mark@mark.mielke.cc writes:
> WAL file is never appended - only re-written?

> If so, then I'm wrong, and ext2 is fine. The requirement is that no
> file system structures change as a result of any writes that
> PostgreSQL does. If no file system structures change, then I take
> everything back as uninformed.

That risk certainly exists in the general data directory, but AFAIK
it's not a problem for pg_xlog.

			regards, tom lane