Seriously it's safe to use rbd cache for vm. Rbd cache behavior like disk cache which is flushed via "fsync" or "fdatasync" calls. A serious application will take care of it. On Fri, Aug 22, 2014 at 7:05 PM, Yufang Zhang <yufang521247 at gmail.com> wrote: > Hi guys, > > Apologize if this question has been asked before. I'd like to know if it is > safe to enable rbd cache with qemu (cache mode set as writeback) in > production? Currently, there are 4 types of guest os supported in our > production: REHL5, RHEL6, Win2k3, Win2k8. Our host is RHEL6.2 on which qemu > supports 'barrier-passing'. Thus we have confident that RHEL6 guests(with > barrier enabled by default) could work well with rbd cache enabled. But as > for REHL5, Win2k3 and Win2k8, I am not sure if it is 100% safe on scenarios > such as guest crash, host crash or power loss. Could anybody give some > suggestion? Really appreciate your help. > > Yufang > > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- Best Regards, Wheat
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