From mboxrd@z Thu Jan  1 00:00:00 1970
From: jim owens <jowens@hp.com>
Subject: Re: thin provisioned LUN support & file system allocation policy
Date: Fri, 07 Nov 2008 10:26:04 -0500
Message-ID: <49145E0C.4030705@hp.com>
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To: Ric Wheeler <rwheeler@redhat.com>
Cc: Theodore Tso <tytso@mit.edu>, Jens Axboe <jens.axboe@oracle.com>, Chris Mason <chris.mason@oracle.com>, Dave Chinner <david@fromorbit.com>, David Woodhouse <dwmw2@infradead.org>, James Bottomley <James.Bottomley@HansenPartnership.com>, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, Black_David@emc.com, "Martin K. Petersen" <martin.petersen@oracle.com>, Tom Coughlan <coughlan@redhat.com>, Matthew Wilcox <matthew@wil.cx>
List-Id: linux-scsi@vger.kernel.org

Ric Wheeler wrote:

> The type of allocation that would help most is something that tries to 
> keep the lower block ranges "hot" for allocation, second best policy 
> would simply keep the allocated blocks in each block group hot and 
> re-allocate them.

This block reuse policy ignores the issue of wear leveling...
as in most design things, trading one problem for another.

jim