On Thu, May 09, 2013 at 01:47:51PM -0700, Darrick J. Wong wrote: > Create a new 'flush' message that causes the dmcache to write all of its > metadata out to disk. This enables us to ensure that the disk reflects > whatever's in memory without having to tear down the cache device. This helps > me in the case where I have a cached ro fs that I can't umount and therefore > can't tear down the cache device, but want to save the cache metadata anyway. > The command syntax is as follows: > > # dmsetup message mycache 0 flush now Nack. [Ignoring the ugly 'now' parameter.] I think you're in danger of hiding the real issue. Which is if the target's destructor and post suspend is not being called then, as far as dm-cache is concerned this is a crash. Any open transactions will be lost as it automatically rolls back. We need to understand more why this is happening. It's actually harmless atm for dm-cache, because we're forced to commit before using a new migration. But for dm-thin you can lose writes. Why are you never tearing down your dm devices? - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
