[CentOS] Does anyone using dm-cache?

Hi,

Has, or does, anyone use dm-cache - specifically for caching SAN based
storage locally?

I'm looking for a way to speed up SAN based storage on a CentOS 5.6 +
XEN Hypervisor which uses iSCSI mounted SAN storage. dm-cache seems
like it do the trick, but I've never heard of it before until someone
mentioned it in another mailing list. A quick search on google didn't
really give me much in terms of actual user experience.

Does anyone use it?
Any feedback? Pitfalls? Success stories?

-- 
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
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