Messages in this thread | | | Date | Wed, 20 Nov 2013 00:04:40 -0800 | From | Christoph Hellwig <> | Subject | Re: [Regression x2, 3.13-git] virtio block mq hang, iostat busted on virtio devices |
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On Tue, Nov 19, 2013 at 02:43:51PM -0700, Jens Axboe wrote: > No, the nr_requests isn't actually relevant in the blk-mq context, the > driver sets its own depth. For the above, it's 64 normal commands, and 2 > reserved. The reserved would be for a flush, for instance. If someone > attempts to queue more than the allocated number of requests, it'll stop > the blk-mq queue and kick things into gear on the virtio side. Then when > requests complete, we start the queue again.
Btw, any reason we lowerered the queue depth from 128 to 64 in virtio-blk?
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