[libvirt] [PATCH] set cache=off on -disk line in qemu driver if <shareable/> (but not <readonly/>) is set.

Daniel P. Berrange berrange at redhat.com
Mon Nov 3 12:05:41 UTC 2008

On Sat, Nov 01, 2008 at 06:20:27PM -0500, Charles Duffy wrote:
> As cache=off is necessary for clustering filesystems such as GFS (and 
> such is the point of shareable, yes?), I believe this is correct behavior.

Yes, I believe you are correct. On a single host our current setup is
sufficient, but if several VMs on different hosts are accessing the 
same underlying shared storage, then we do need to disable the caching
of reads. So cache=off for <shared> disks is the safest option.

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