Re: [gentoo-user] planned btrfs conversion: questions

[William Kenworthy <billk@iinet.net.au>]

On 05/08/14 19:57, William Kenworthy wrote:
> On 05/07/14 07:51, Marc Joliet wrote:
>> Am Wed, 07 May 2014 06:56:12 +0800
>> schrieb William Kenworthy <billk@iinet.net.au>:
>>
>>> On 05/06/14 18:18, Marc Joliet wrote:
>>>> Hi all,
>>>>
>>>> I've become increasingly motivated to convert to btrfs.  From what I've seen,
>>>> it has become increasingly stable; enough so that it is apparently supposed to
>>>> become the default FS on OpenSuse in 13.2.
>>>>
>>>> I am motivated by various reasons:
>>> ....
>>>

scrub status for 20a18d40-e4e6-4e94-88e6-23eacd629cba
        scrub started at Sat May 10 14:27:35 2014, running for 10520 seconds
        total bytes scrubbed: 676.67GiB with 2 errors
        error details: csum=2
        corrected errors: 0, uncorrectable errors: 2, unverified errors: 0

and from /var/log/messages

May 10 16:15:26 moriah kernel: btrfs: checksum error at logical
486690582528 on dev /dev/mapper/vg1-backups, sector 965263992, root 5,
inode 10156876, offset 3179999232, length 4096, links 1 (path:
olympus/20140426/tree/mnt/data/vm/asterisk/asterisk_disk1.qcow2)
May 10 16:15:26 moriah kernel: btrfs: bdev /dev/mapper/vg1-backups errs:
wr 0, rd 14, flush 0, corrupt 11, gen 0
May 10 16:15:26 moriah kernel: btrfs: unable to fixup (regular) error at
logical 486690582528 on dev /dev/mapper/vg1-backups


I'll delete the file(s) (its just one of numerous dated backups)

No event I can put it down to, nothing I can find in the logs - just
happens on an irregular basis!

Its btrfs using compress=LZO on an LVM2 partition after running a few
dirvish multiple backup sessions.  Note that as I said in my original
email, "dirvish" really hammers a file system and only reiserfs seems to
withstand it though I have gotten errors with it in the past.  Ive tried
ext4 (takes only a couple of backup sessions and its unrecoverable,
btrfs an occasional error with two complete losses of the
partition/filesystem since Christmas and reiserfs gets rare errors.

Note that hardware and other items have been changed over time so I
doubt its a specific problem there.

Not quite there yet ...

BillK