Konstantinos Skarlatos
2014-Jun-17 21:35 UTC
commit 762380a "block: add notion of a chunk size for request merging" stops io on btrfs
Hi all,
with 3.16-rc1 rsync stops writing to my btrfs filesystem and stays at a
D+ state.
git bisect showed that the problematic commit is:
762380ad9322951cea4ce9d24864265f9c66a916 is the first bad commit
commit 762380ad9322951cea4ce9d24864265f9c66a916
Author: Jens Axboe <axboe@fb.com>
Date: Thu Jun 5 13:38:39 2014 -0600
block: add notion of a chunk size for request merging
Some drivers have different limits on what size a request should
optimally be, depending on the offset of the request. Similar to
dividing a device into chunks. Add a setting that allows the driver
to inform the block layer of such a chunk size. The block layer will
then prevent merging across the chunks.
This is needed to optimally support NVMe with a non-zero stripe size.
Signed-off-by: Jens Axboe <axboe@fb.com>
sysrq w gives:
[ 3287.169569] SysRq : Show Blocked State
[ 3287.169655] task PC stack pid father
[ 3287.169675] rsync D 0000000000000001 0 626 613
0x00000000
[ 3287.169685] ffff8802037c7d08 0000000000000082 ffff8800cf2e7010
0000000000014500
[ 3287.169693] ffff8802037c7fd8 0000000000014500 ffff8800cf2e7010
ffff8802037c7c98
[ 3287.169700] 0000000000000292 0000000000000292 ffff8802037c7c50
ffff8802037c7c50
[ 3287.169706] Call Trace:
[ 3287.169722] [<ffffffff814f71d2>] ? do_page_fault+0x22/0x30
[ 3287.169733] [<ffffffff8101cd89>] ? read_tsc+0x9/0x20
[ 3287.169743] [<ffffffff811379d0>] ? sleep_on_page+0x20/0x20
[ 3287.169749] [<ffffffff814eff29>] schedule+0x29/0x70
[ 3287.169756] [<ffffffff814f0214>] io_schedule+0x94/0xf0
[ 3287.169763] [<ffffffff811379de>] sleep_on_page_killable+0xe/0x50
[ 3287.169770] [<ffffffff814f0748>] __wait_on_bit_lock+0x48/0xb0
[ 3287.169777] [<ffffffff8128c753>] ? radix_tree_lookup_slot+0x13/0x30
[ 3287.169785] [<ffffffff81137b7a>] __lock_page_killable+0x6a/0x70
[ 3287.169792] [<ffffffff810acec0>] ? autoremove_wake_function+0x40/0x40
[ 3287.169799] [<ffffffff811398c8>] generic_file_aio_read+0x458/0x6a0
[ 3287.169808] [<ffffffff811ab63a>] do_sync_read+0x5a/0x90
[ 3287.169816] [<ffffffff811abc47>] vfs_read+0x97/0x160
[ 3287.169823] [<ffffffff811ac886>] SyS_read+0x46/0xc0
[ 3287.169831] [<ffffffff814fb969>] system_call_fastpath+0x16/0x1b
$ btrfs filesystem show /storage/btrfs
Label: none uuid: bde3c349-9e08-45bb-8517-b9a6dda81e88
Total devices 6 FS bytes used 8.58TiB
devid 1 size 3.64TiB used 3.02TiB path /dev/sdf
devid 2 size 1.82TiB used 1.20TiB path /dev/sda
devid 3 size 1.82TiB used 1.20TiB path /dev/sdb
devid 4 size 1.82TiB used 1.20TiB path /dev/sdc
devid 5 size 1.82TiB used 1.20TiB path /dev/sdd
devid 6 size 1.82TiB used 1.20TiB path /dev/sdh
Btrfs v3.14.2-dirty
$ btrfs fi df /storage/btrfs
Data, single: total=8.89TiB, used=8.51TiB
System, RAID1: total=32.00MiB, used=992.00KiB
Metadata, RAID1: total=69.00GiB, used=67.83GiB
unknown, single: total=512.00MiB, used=0.00
full dmesg attached
Please CC me if replying on LKML, as I am not subscribed there