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Message-ID: <e2e108260805062315n15e84abck5f4207a6a7a11805@mail.gmail.com>
Date: Wed, 7 May 2008 08:15:23 +0200
From: "Bart Van Assche" <bart.vanassche@gmail.com>
To: "Yigal Sadgat" <YSadgat1@gcte.com>
Subject: Re: Compact Flash Question
Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org,
       jwboyer@linux.vnet.ibm.com, joern@logfs.org
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On Tue, May 6, 2008 at 11:59 PM, Yigal Sadgat <YSadgat1@gcte.com> wrote:
> (2) An engineer at SanDisk Engineering told me NOT to do wear leveling.
> The file allocation table is written very frequently back into the flash. So
> is it really safe to assume that I don't need wear leveling???

For most Linux filesystems you really need wear leveling. E.g. ext3's
superblock is at a fixed location and gets overwritten frequently.
Without wear leveling you risk that the flash sector where the
superblock resides wears out early.

When using ext3 on a CompactFlash, you can limit the number of writes
to the CompactFlash significantly by mounting the medium with
parameters like noatime,nodiratime,commit=300.

Bart.