On Thu, Nov 14, 2019 at 12:13:24AM -0500, Zygo Blaxell wrote: > On Fri, Nov 01, 2019 at 04:09:08PM +0100, David Sterba wrote: > > The raid1c34 patches are not intrusive and could be backported on top of > > 5.3 because all the preparatory work has been merged already. > > Indeed, that's how I ended up testing them. I couldn't get the 5.4-rc > kernels to run long enough to do meaningful testing before they locked > up. I tested with 5.3.8 + patches. > > I left out the last patch that removes the raid1c3 incompat flag because > 5.3 didn't have the block group tree code to apply it to. > > I ran my raid1 and raid56 corruption recovery tests modified for raid1c3. > The first test is roughly: > > mkfs.btrfs -draid1c3 -mraid1c3 /dev/vd[bcdef] > mount /dev/vdb /test > cp -a 9GB_data /test > sync > sysctl vm.drop_caches=3 > diff -r 9GB_data /test > head -c 9g /dev/urandom > /dev/vdb > head -c 9g /dev/urandom > /dev/vdc > sync > sysctl vm.drop_caches=3 > diff -r 9GB_data /test > btrfs scrub start -Bd /test > sysctl vm.drop_caches=3 > diff -r 9GB_data /test > btrfs scrub start -Bd /test > sysctl vm.drop_caches=3 > diff -r 9GB_data /test > > First scrub reported a lot of corruption on /dev/vdb and /dev/vdc. Second > scrub reported no errors. diff (all instances) reported no differences. > > Second test is: > > mkfs.btrfs -draid6 -mraid1c3 /dev/vd[bcdef] > # rest as above... > > Similar results: first scrub reported many errors as expected. > Second scrub reported no errors. No diffs. Thanks for the tests.
