From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alex Zhuravlev <Alex.Zhuravlev@Sun.COM>
Date: Mon, 30 Jun 2008 15:04:14 +0400
Subject: [Lustre-devel] some thoughts on COS
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References: <C46FF0A8.591A%peter.braam@sun.com> <486894E9.1030104@sun.com>
	<18536.45369.176085.583659@gargle.gargle.HOWL>
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Nikita Danilov wrote:
> Alex Zhuravlev writes:
>  > Hi,
>  > 
>  > all access to an object can be broken into 3 phases:
>  > 1) lock is acquired and used to modify data, no concurrent
>  >     access as data is inconsistent
>  > 2) data is consistent, but uncommitted; thus same client can
>  >     access data, others can not
> 
> Other clients cannot read uncommitted data, but they can safely
> overwrite them. Do we care about such use cases?

this is true for data, but most of metadata operations do read first.

thanks, Alex