On Sun, Nov 14, 2021 at 08:51:01PM +0800, Qu Wenruo wrote: > In the coming btrfs-progs v5.15 release, mkfs.btrfs will change to use > v2 cache by default. > > However nospace_cache mount option will not work with v2 cache, as it > would make v2 cache out of sync with on-disk used space. > > So mounting a btrfs with v2 cache using "nospace_cache" will make btrfs > to reject the mount. > > There are quite some test cases relying on nospace_cache to prevent v1 > cache to take up data space. > > For those test cases, we no longer need the "nospace_cache" mount option > if the filesystem is already using v2 cache. > Since v2 cache is using metadata space, it will no longer take up data > space, thus no extra mount options for those test cases. > > By this, we can keep those existing tests to run without problem for > both v1 and v2 cache. > > Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx> Thanks, this explains a weird failure state that I've been seeing with btrfs/199 writing into /tmp and filling everything, which causes the rest of the tests to fail. Josef
