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Re: Proposal: B_ARRIER (addresses wapbl performance?)

On Dec 9, 2008, at 2:16 AM, Manuel Bouyer wrote:

I'm not even sure FUA is necessery, if the ordered tag is working
properly (i.e. the device doesn't merge different writes in its cache,
which would break ordering).

Repeat: Ordered tags have nothing to do with whether or not a write is committed to stable storage. But that is precisely what you want for a write to a journal. FUA is the mechanism that is specifically intended to get the behavior you want for a journal.

Manuel Bouyer <>
    NetBSD: 26 ans d'experience feront toujours la difference

-- thorpej

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