On Mon, Feb 26, 2018 at 10:20 AM, Qu Wenruo <quwenruo.btrfs@xxxxxxx> wrote: > > > On 2018年02月26日 16:15, Amir Goldstein wrote: >> On Mon, Feb 26, 2018 at 9:31 AM, Qu Wenruo <wqu@xxxxxxxx> wrote: >>> This test case is originally designed to expose unexpected corruption >>> for btrfs, where there are several reports about btrfs serious metadata >>> corruption after power loss. >>> >>> The test case itself will trigger heavy fsstress for the fs, and use >>> dm-flakey to emulate power loss by dropping all later writes. >>> >> >> Come on... dm-flakey is so 2016 >> You should take Josef's fsstress+log-writes test and bring it to fstests: >> https://github.com/josefbacik/log-writes >> >> By doing that you will gain two very important features from the test: >> >> 1. Problems will be discovered much faster, because the test can run fsck >> after every single block write has been replayed instead of just at random >> times like in your test > > That's what exactly I want!!! > > Great thanks for this one! I would definitely look into this. > (Although the initial commit is even older than 2016) > Please note that Josef's replay-individual-faster.sh script runs fsck every 1000 writes (i.e. --check 1000), so you can play with this argument in your test. Can also run --fsck every --check fua or --check flush, which may be more indicative of real world problems. not sure. > > But the test itself could already expose something on EXT4, it still > makes some sense for ext4 developers as a verification test case. > Please take a look at generic/456 When generic/455 found a reproduciable problem in ext4, I created a specific test without any randomness to pin point the problem found (using dm-flakey). If the problem you found is reproduciable, then it will be easy for you to create a similar "bisected" test. Thanks, Amir.
