On Wed, Jan 18, 2012 at 2:58 PM, Darrick J. Wong <djwong at us.ibm.com> wrote: > Or possibly modify md-raid5 not to snapshot dirty pages prior to xor/write? > (I never really bothered to find out if it really does this.) It does. ops_run_biodrain() copies from bio to the stripe cache before performing xor. -- Dan