[Xen-devel] [PATCH] Segments can span multiple clusters with tap

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Subject:	[Xen-devel] [PATCH] Segments can span multiple clusters with tap:qcow
From:	Mark McLoughlin <markmc@xxxxxxxxxx>
Date:	Wed, 25 Apr 2007 21:41:19 +0100
Delivery-date:	Wed, 25 Apr 2007 13:40:03 -0700
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Hey,
        In blktap's qcow we need split up read/write requests if the requests
span multiple clusters. However, with our MAX_AIO_REQUESTS define we
assume that there is only ever a single aio request per tapdisk request
and under heavy i/o we can run out of room causing us to cancel
requests.

        The attached patch dynamically allocates (based on cluster_bits) the
various io request queues the driver maintains.

  Signed-off-by: Mark McLoughlin <markmc@xxxxxxxxxx>

Cheers,
Mark.

block-qcow-multiple-aio-requests-per-segment.patch
Description: Text Data

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[Xen-devel] [PATCH] Segments can span multiple clusters with tap:qcow