On 06/05/2012 09:23 PM, Christoph Hellwig wrote: > On Tue, Jun 05, 2012 at 09:20:30PM +0800, Liu Yuan wrote: >> You meant the requests from Guest could be overlapped? Disk is seen by >> guest OS as an array of blocks, I can't imagine any sane driver issue >> overlapped requests to disk drive controller. > > Yes, we've seen overlapping or duplicate requests from the OS. > > Assuming any sort of sanity from the OS is unfortunately not an option > in virtualized environments.
This would be something odd, but we have to face up with. Well, then there might be problems with overlapped requests: Ordering: 1 over network, the requests seen by Sheepdog might not be the same as is from Guest. 2 how do we deal with overlapped read/write, write/write pair? Looks to me, even with locks, we can't cope with it. Thanks, Yuan -- sheepdog mailing list [email protected] http://lists.wpkg.org/mailman/listinfo/sheepdog
