From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Thornber <thornber@redhat.com>
Subject: Re: Review of dm-block-manager.c
Date: Tue, 2 Aug 2011 14:29:00 +0100
Message-ID: <20110802132859.GA28866@ubuntu>
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	<20110802130755.GA26994@ubuntu>
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On Tue, Aug 02, 2011 at 02:07:55PM +0100, Joe Thornber wrote:
> There isn't that degree of parallelism.  We can't have multiple
> threads pulling the cache in different directions for performance
> reasons.  So we have multiple threads that use this in a non-blocking
> mode.  ie. they use the try_lock variants, and only get the data if
> it's already available in the cache.  If the non-blocking requests
> failed then it gets passed across for a worker thread to deal with.
> This is the only thread that updates the cache.  There is no issue
> here.

In fact because we have only a single mutator the block recycling
concerns are not an issue for thinp, though they should still be
fixed.

- Joe