FYI: Looks like patch: Btrfs: fix read corruption of compressed and shared extents Partial fixed my issue 2015-08-26 22:33 GMT+03:00 Timofey Titovets <nefelim4ag@xxxxxxxxx>: > Hello guys, > i like btrfs, and i want put it in production soon, > one of the feature that i want use, is a deduplication. > > i frequently testing duperemove on btrfs and already see this problem before. > i know what btrfs before, change mtime while deduping, but after dedup > fixes from Mark (https://github.com/markfasheh), i've try to get > checksums. > > As i know duperemove use kernel ioctl for deduping, i.e. it's not a > duperemove issue, kernel must keep data consistent. > > File system is fresh and btrfs check not show any metadata corruption. > > Github issue: > https://github.com/markfasheh/duperemove/issues/91 > > System info: > $ uname -a > Linux titovetst-beplan 4.2.0-rc8-next-20150825-0959-ARCH #1 SMP Wed > Aug 26 10:27:18 MSK 2015 x86_64 GNU/Linux > > Mount options: > rw,relatime,compress=lzo,space_cache,subvolid=257,subvol=/@home > > Okay, how i find it: > > md5sum_recursive(){ > find $@ -type f -exec md5sum {} \; > } > > cp -av --reflink=always ~/<src> ~/<dest> > md5sum_recursive ~/<dest> > ~/dedup.before > duperemove -vhrdb 8k ~/<dest> > md5sum_recursive ~/<dest> > ~/dedup.after > diff -up ~/dedup.before ~/dedup.after > > what i've got (full diff in attach): > --- /home/nefelim4ag/dedup.after 2015-08-26 21:36:55.773452558 +0300 > +++ /home/nefelim4ag/dedup.before 2015-08-26 21:21:01.203600761 +0300 > @@ -25139,9 +25139,9 @@ caf9d41036e46b85d90a9541e8bc9ce1 /home/ > .... > -0ccbc9c81a51f59dcf2ac0d102de37cb > /home/nefelim4ag/L4D2/left4dead2/pak01_003.vpk > +e665b502ee977dc1c619ecbd415c91b8 > /home/nefelim4ag/L4D2/left4dead2/pak01_000.vpk > .... > > Files sizes not changed and it's > 1MB. > > Every time i've get a random data corruption. > Only dependencies what i've find it is what smallest block -> more > corruptions and vise versa, i.e. more data deduped -> more corrupted. > > Smart of the disk, it's not looks, like damaged. (attach) > > What i can provide to help fix this issue? > If it's needed, i can recompile kernel with some parameters if it can > help, of course. > > Thanks. > > -- > Have a nice day, > Timofey. -- Have a nice day, Timofey. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
