Okey, I found a patch from Mark 35 weeks ago which was not merged into xfstest:
[PATCH] xfstests/btrfs: add test for quota groups and drop snapshot It looks can answer my question here. Thanx Yang On Mon, Mar 16, 2015 at 12:59 PM, Dongsheng Yang <yangds.f...@cn.fujitsu.com> wrote: > On 03/04/2015 04:20 AM, Mark Fasheh wrote: >> >> On Tue, Mar 03, 2015 at 09:00:36AM -0500, Josef Bacik wrote: >>> >>> On 03/03/2015 06:18 AM, Dongsheng Yang wrote: >>>> >>>> On 02/26/2015 02:05 PM, Dongsheng Yang wrote: >>>>> >>>>> Wait a minute, this patch seems not working well in accounting quota >>>>> number when >>>>> deleting data shared by different subvolumes. >>>>> >>>>> I will investigate more about it and send a V2 out. >>>> >>>> I have sent a fstest >>>> [PATCH] fstest: btrfs: add a test for quota number when deleting a >>>> subvol. >>>> for this problem I was trying to solve in this patch. >>>> >>>> Please consider reverting the two commits introduced the problem: >>>> >>>> e339a6b0 (Btrfs: __btrfs_mod_ref should always use no_quota) >>>> 1152651a (btrfs: qgroup: account shared subtrees during snapshot delete) >>>> >>> We aren't reverting these two commits, what we had was worse before than >>> it >>> is now. We need to figure out why this is resulting in problems and fix >>> that rather than throwing out a whole bunch of work. Thanks, >> >> Agreed, reverting these would re-introduce far more problems than it would >> solve. > > > Hi Josef and Mark, > > Sorry for the late. > > Thanx for your reply and sorry I am not clear about the "far more problems". > > From the result below, I saw there are some diff reports in V4.0-rc1 and > when I > revert these two commits. It's consistent now. > > But I think there must be something I am missing. I am glad to investigate > more > about it and solve it. But at first I need to know what's the problem > SUBTREE is > trying to solve. > > Example: > mkfs.btrfs /dev/sdc -f > mount /dev/sdc /mnt > btrfs quota enable /mnt > btrfs sub create /mnt/sub > dd if=/dev/zero of=/mnt/sub/data bs=1024 count=1000 > btrfs sub snapshot /mnt/sub /mnt/snap > btrfs qgroup create 1/1 /mnt > btrfs qgroup assign 0/257 1/1 /mnt > btrfs quota rescan -w /mnt > sync > btrfs sub delete /mnt/sub > ----------------------- <-------------wait for cleaner_kthread. > btrfs qgroup show /mnt > umount /mnt > btrfs check --qgroup-report /dev/sdc |grep diff > > Result: > (1). V4.0-rc1 > # btrfs qgroup show /mnt > qgroupid rfer excl > -------- ---- ---- > 0/5 16.00KiB 16.00KiB > 0/257 1000.00KiB 0.00B > 0/258 1016.00KiB 1016.00KiB > 1/1 1000.00KiB 0.00B > # btrfs check --qgroup-report /dev/sdc |grep diff > Counts for qgroup id: 257 are different > diff: referenced -1024000 referenced compressed -1024000 > Counts for qgroup id: 281474976710657 are different > diff: referenced -1024000 referenced compressed -1024000 > > (2). V4.0-rc1 with reverts of "96c92f" and "c04cad" > # btrfs qgroup show /mnt > qgroupid rfer excl > -------- ---- ---- > 0/5 16.00KiB 16.00KiB > 0/257 0.00B 0.00B > 0/258 1016.00KiB 1016.00KiB > 1/1 0.00B 0.00B > # btrfs check --qgroup-report /dev/sdc |grep diff > # > *No diff in btrfs check --qgroup-report* > > > Thanx >> >> --Mark >> >> -- >> Mark Fasheh >> . >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
