On 19/02/11 23:22, Pádraig Brady wrote: > On 19/02/11 18:28, Mike Frysinger wrote: >> based on other threads (which i havent been following too closely), did we >> settle on this being a btrfs bug ? >> -mike > > Nope, cp 8.10 is not absolved yet. > It may be btrfs not honoring FIEMAP_FLAG_SYNC, > and/or it may be cp needing to handle FIEMAP_EXTENT_ENCODED > specially. > > It would help if you ran `sync` before the copy, > to exclude that as a possible issue. > > Also `filefrag -v` output for the file on > the compressed BTRFS file system would be helpful.
Hmm I just tried the latest Fedora 15 live image and was tripped up a bit by https://bugzilla.redhat.com/show_bug.c Anyway it uses 2.6.38 rc4 and "compress" doesn't seem to be implemented for BTRFS there? Writing a file of zeros showed a normal disk usage, and filefrag -v didn't report any flags for the extents. In any case, cp/fiemap-2 passed on each of about 100 runs, even without introducing and syncs. cheers, Pádraig.
