Am Wed, 11 Jan 2017 18:34:17 +0100 schrieb Jan Wiele <jan@xxxxxxxxx>: > Hi, > I'm experiencing a possible bcache-hang in my setup. > > Mainboard: Asrock Rack EP2C602 > CPU: 2x Intel Xeon E5-2670 > Linux: 4.8.13-1-ARCH > Cache-device: Partition on Samsung SSD 850 EVO 500GB > Backing-device: 500GB Western Digital Black > > > Bcache is running in writeback mode. On top of bcache, I'm running > LVM, which provides a Games-LV for a Qemu Windows-10 VM (Games-HD > with drive letter 'D'. Drive C is hosted on a non-bcache block > device. Each VM has its own GPU via passthrough). For a second/third > VM, I create snapshots of the Games-LV. > > When playing the game Overwatch, the first VM suddenly stops to > respond (after about >20min), some seconds later the second VM, too. > > Currently I'm not near the machine with the problem, but I'm > appending as much information as possible. Bcache doesn't seem to be involved in the backtrace - at least I couldn't spot it but I'm not a kernel dev. Are you maybe using bfq block scheduler? Try to switch to deadline and see if the problem persists. I personally had similar problems with bfq. > Regards, > Jan > > > > $ bcache-super-show /dev/sdb6 > sb.magic ok > sb.first_sector 8 [match] > sb.csum 617AC6C2ABF15A0D [match] > sb.version 3 [cache device] > > dev.label (empty) > dev.uuid 73ec71d1-1353-4cc0-8b06-d798b44d593e > dev.sectors_per_block 1 > dev.sectors_per_bucket 1024 > dev.cache.first_sector 1024 > dev.cache.cache_sectors 204692480 > dev.cache.total_sectors 204693504 > dev.cache.ordered yes > dev.cache.discard no > dev.cache.pos 0 > dev.cache.replacement 0 [lru] > > cset.uuid 025ec95a-c03b-481f-97e4-d6dab92ba6b1 > > $ dmesg > [...] > [ 3945.367318] INFO: task kworker/22:0:146 blocked for more than 120 > seconds. [ 3945.369245] Not tainted 4.8.13-1-ARCH #1 > [ 3945.371113] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this message. [ 3945.372970] kworker/22:0 D > ffff88046d2c3cd8 0 146 2 0x00000000 [ 3945.372982] > Workqueue: events update_writeback_rate [bcache] [ 3945.372983] > ffff88046d2c3cd8 00ff88046d2c3cd0 ffff88046148e3c0 ffff88046d270e40 > [ 3945.372986] ffff88046fd97ff0 ffff88046d2c4000 ffff8804696f0ad8 > ffff88046d2c3d10 [ 3945.372988] ffff8804696f0af0 ffff8804696f0b18 > ffff88046d2c3cf0 ffffffff815f40ec [ 3945.372990] Call Trace: > [ 3945.372995] [<ffffffff815f40ec>] schedule+0x3c/0x90 > [ 3945.372997] [<ffffffff815f6669>] > rwsem_down_read_failed+0xf9/0x150 [ 3945.372999] > [<ffffffff8130bb08>] call_rwsem_down_read_failed+0x18/0x30 > [ 3945.373000] [<ffffffff815f5f07>] down_read+0x17/0x30 > [ 3945.373004] [<ffffffffa0056dc5>] update_writeback_rate+0x25/0x210 > [bcache] [ 3945.373006] [<ffffffff81095ef5>] > process_one_work+0x1e5/0x470 [ 3945.373008] [<ffffffff810961c8>] > worker_thread+0x48/0x4e0 [ 3945.373009] [<ffffffff81096180>] ? > process_one_work+0x470/0x470 [ 3945.373011] [<ffffffff8109be38>] > kthread+0xd8/0xf0 [ 3945.373014] [<ffffffff8102c782>] ? > __switch_to+0x2d2/0x630 [ 3945.373016] [<ffffffff815f823f>] > ret_from_fork+0x1f/0x40 [ 3945.373018] [<ffffffff8109bd60>] ? > kthread_worker_fn+0x170/0x170 [ 3945.373031] INFO: task > bcache_writebac:343 blocked for more than 120 seconds. > [ 3945.374945] Not tainted 4.8.13-1-ARCH #1 [ 3945.376837] > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this > message. [ 3945.378724] bcache_writebac D ffff88046975fcb8 0 > 343 2 0x00000000 [ 3945.378735] ffff88046975fcb8 > 00ff88046fa17f80 ffffffff81a0d500 ffff88046978d580 [ 3945.378737] > ffff88046978d500 ffff880469760000 ffff8804696f0ad8 ffff8804696f0ad8 > [ 3945.378740] ffff8804696f0af0 ffffffff00000001 ffff88046975fcd0 > ffffffff815f40ec [ 3945.378742] Call Trace: [ 3945.378744] > [<ffffffff815f40ec>] schedule+0x3c/0x90 [ 3945.378746] > [<ffffffff815f67f2>] rwsem_down_write_failed+0x132/0x2b0 > [ 3945.378748] [<ffffffff8130bb37>] > call_rwsem_down_write_failed+0x17/0x30 [ 3945.378750] > [<ffffffff815f5f44>] down_write+0x24/0x40 [ 3945.378754] > [<ffffffffa005747b>] bch_writeback_thread+0x6b/0x7f0 [bcache] > [ 3945.378758] [<ffffffffa0057410>] ? write_dirty+0xb0/0xb0 [bcache] > [ 3945.378762] [<ffffffff8109be38>] kthread+0xd8/0xf0 > [ 3945.378763] [<ffffffff8102c782>] ? __switch_to+0x2d2/0x630 > [ 3945.378765] [<ffffffff815f823f>] ret_from_fork+0x1f/0x40 > [ 3945.378767] [<ffffffff8109bd60>] ? kthread_worker_fn+0x170/0x170 > [ 3945.378777] INFO: task qemu-system-x86:829 blocked for more than > 120 seconds. [ 3945.380619] Not tainted 4.8.13-1-ARCH #1 > [ 3945.382501] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this message. [ 3945.385458] qemu-system-x86 D > ffff88046933b7a8 0 829 1 0x00000000 [ 3945.385461] > ffff88046933b7a8 00ff88046933b7b0 ffff8808650faac0 ffff88086ab52ac0 > [ 3945.385463] 8000000000000000 ffff88046933c000 ffff8804696f0ad8 > ffff88046933b7e0 [ 3945.385465] ffff8804696f0af0 ffff8804696f0000 > ffff88046933b7c0 ffffffff815f40ec [ 3945.385467] Call Trace: > [ 3945.385470] [<ffffffff815f40ec>] schedule+0x3c/0x90 > [ 3945.385471] [<ffffffff815f6669>] > rwsem_down_read_failed+0xf9/0x150 [ 3945.385475] > [<ffffffffa00457db>] ? bch_submit_bbio+0x2b/0x30 [bcache] > [ 3945.385477] [<ffffffff8130bb08>] > call_rwsem_down_read_failed+0x18/0x30 [ 3945.385478] > [<ffffffff815f5f07>] down_read+0x17/0x30 [ 3945.385482] > [<ffffffffa004ab9b>] cached_dev_make_request+0x63b/0xcb0 [bcache] > [ 3945.385485] [<ffffffff812cd0e2>] generic_make_request+0xf2/0x1a0 > [ 3945.385487] [<ffffffff812cd20d>] submit_bio+0x7d/0x150 > [ 3945.385490] [<ffffffff8124a1e3>] > __blockdev_direct_IO+0x31a3/0x4040 [ 3945.385493] > [<ffffffff8121d2dd>] ? poll_freewait+0x8d/0xb0 [ 3945.385495] > [<ffffffff81244520>] ? I_BDEV+0x20/0x20 [ 3945.385497] > [<ffffffff81244e43>] blkdev_direct_IO+0x43/0x50 [ 3945.385500] > [<ffffffff81179b04>] generic_file_direct_write+0xb4/0x170 > [ 3945.385502] [<ffffffff81179c7b>] > __generic_file_write_iter+0xbb/0x1d0 [ 3945.385504] > [<ffffffff81205d34>] ? __check_object_size+0x54/0x1d6 [ 3945.385506] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 3945.385508] > [<ffffffff8124603b>] blkdev_write_iter+0x8b/0x100 [ 3945.385509] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 3945.385511] > [<ffffffff8131235a>] ? import_iovec+0x3a/0xe0 [ 3945.385514] > [<ffffffff81259407>] aio_run_iocb+0x247/0x2c0 [ 3945.385516] > [<ffffffff81256586>] ? eventfd_ctx_read+0x166/0x1e0 [ 3945.385518] > [<ffffffff8121d4c0>] ? poll_select_copy_remaining+0x150/0x150 > [ 3945.385519] [<ffffffff810a6c00>] ? wake_up_q+0x80/0x80 > [ 3945.385521] [<ffffffff81227567>] ? __fget+0x77/0xb0 > [ 3945.385522] [<ffffffff81227605>] ? __fget_light+0x25/0x60 > [ 3945.385524] [<ffffffff81227653>] ? __fdget+0x13/0x20 > [ 3945.385526] [<ffffffff8125ade4>] do_io_submit+0x364/0x590 > [ 3945.385528] [<ffffffff8125b020>] SyS_io_submit+0x10/0x20 > [ 3945.385530] [<ffffffff815f8032>] > entry_SYSCALL_64_fastpath+0x1a/0xa4 [ 4068.241562] INFO: task > kworker/22:0:146 blocked for more than 120 seconds. > [ 4068.243485] Not tainted 4.8.13-1-ARCH #1 [ 4068.245395] > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this > message. [ 4068.247346] kworker/22:0 D ffff88046d2c3cd8 0 > 146 2 0x00000000 [ 4068.247354] Workqueue: events > update_writeback_rate [bcache] [ 4068.247355] ffff88046d2c3cd8 > 00ff88046d2c3cd0 ffff88046148e3c0 ffff88046d270e40 [ 4068.247358] > ffff88046fd97ff0 ffff88046d2c4000 ffff8804696f0ad8 ffff88046d2c3d10 > [ 4068.247360] ffff8804696f0af0 ffff8804696f0b18 ffff88046d2c3cf0 > ffffffff815f40ec [ 4068.247406] Call Trace: [ 4068.247409] > [<ffffffff815f40ec>] schedule+0x3c/0x90 [ 4068.247411] > [<ffffffff815f6669>] rwsem_down_read_failed+0xf9/0x150 > [ 4068.247413] [<ffffffff8130bb08>] > call_rwsem_down_read_failed+0x18/0x30 [ 4068.247415] > [<ffffffff815f5f07>] down_read+0x17/0x30 [ 4068.247418] > [<ffffffffa0056dc5>] update_writeback_rate+0x25/0x210 [bcache] > [ 4068.247421] [<ffffffff81095ef5>] process_one_work+0x1e5/0x470 > [ 4068.247422] [<ffffffff810961c8>] worker_thread+0x48/0x4e0 > [ 4068.247424] [<ffffffff81096180>] ? process_one_work+0x470/0x470 > [ 4068.247426] [<ffffffff8109be38>] kthread+0xd8/0xf0 > [ 4068.247427] [<ffffffff8102c782>] ? __switch_to+0x2d2/0x630 > [ 4068.247429] [<ffffffff815f823f>] ret_from_fork+0x1f/0x40 > [ 4068.247432] [<ffffffff8109bd60>] ? kthread_worker_fn+0x170/0x170 > [ 4068.247439] INFO: task bcache_writebac:343 blocked for more than > 120 seconds. [ 4068.249394] Not tainted 4.8.13-1-ARCH #1 > [ 4068.251285] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this message. [ 4068.253194] bcache_writebac D > ffff88046975fcb8 0 343 2 0x00000000 [ 4068.253196] > ffff88046975fcb8 00ff88046fa17f80 ffffffff81a0d500 ffff88046978d580 > [ 4068.253199] ffff88046978d500 ffff880469760000 ffff8804696f0ad8 > ffff8804696f0ad8 [ 4068.253201] ffff8804696f0af0 ffffffff00000001 > ffff88046975fcd0 ffffffff815f40ec [ 4068.253203] Call Trace: > [ 4068.253205] [<ffffffff815f40ec>] schedule+0x3c/0x90 > [ 4068.253207] [<ffffffff815f67f2>] > rwsem_down_write_failed+0x132/0x2b0 [ 4068.253209] > [<ffffffff8130bb37>] call_rwsem_down_write_failed+0x17/0x30 > [ 4068.253211] [<ffffffff815f5f44>] down_write+0x24/0x40 > [ 4068.253214] [<ffffffffa005747b>] bch_writeback_thread+0x6b/0x7f0 > [bcache] [ 4068.253218] [<ffffffffa0057410>] ? write_dirty+0xb0/0xb0 > [bcache] [ 4068.253220] [<ffffffff8109be38>] kthread+0xd8/0xf0 > [ 4068.253221] [<ffffffff8102c782>] ? __switch_to+0x2d2/0x630 > [ 4068.253223] [<ffffffff815f823f>] ret_from_fork+0x1f/0x40 > [ 4068.253225] [<ffffffff8109bd60>] ? kthread_worker_fn+0x170/0x170 > [ 4068.253230] INFO: task qemu-system-x86:829 blocked for more than > 120 seconds. [ 4068.255137] Not tainted 4.8.13-1-ARCH #1 > [ 4068.256969] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > disables this message. [ 4068.258844] qemu-system-x86 D > ffff88046933b7a8 0 829 1 0x00000000 [ 4068.258846] > ffff88046933b7a8 00ff88046933b7b0 ffff8808650faac0 ffff88086ab52ac0 > [ 4068.258848] 8000000000000000 ffff88046933c000 ffff8804696f0ad8 > ffff88046933b7e0 [ 4068.258850] ffff8804696f0af0 ffff8804696f0000 > ffff88046933b7c0 ffffffff815f40ec [ 4068.258853] Call Trace: > [ 4068.258855] [<ffffffff815f40ec>] schedule+0x3c/0x90 > [ 4068.258856] [<ffffffff815f6669>] > rwsem_down_read_failed+0xf9/0x150 [ 4068.258861] > [<ffffffffa00457db>] ? bch_submit_bbio+0x2b/0x30 [bcache] > [ 4068.258863] [<ffffffff8130bb08>] > call_rwsem_down_read_failed+0x18/0x30 [ 4068.258866] > [<ffffffff815f5f07>] down_read+0x17/0x30 [ 4068.258870] > [<ffffffffa004ab9b>] cached_dev_make_request+0x63b/0xcb0 [bcache] > [ 4068.258872] [<ffffffff812cd0e2>] generic_make_request+0xf2/0x1a0 > [ 4068.258874] [<ffffffff812cd20d>] submit_bio+0x7d/0x150 > [ 4068.258877] [<ffffffff8124a1e3>] > __blockdev_direct_IO+0x31a3/0x4040 [ 4068.258879] > [<ffffffff8121d2dd>] ? poll_freewait+0x8d/0xb0 [ 4068.258881] > [<ffffffff81244520>] ? I_BDEV+0x20/0x20 [ 4068.258883] > [<ffffffff81244e43>] blkdev_direct_IO+0x43/0x50 [ 4068.258886] > [<ffffffff81179b04>] generic_file_direct_write+0xb4/0x170 > [ 4068.258887] [<ffffffff81179c7b>] > __generic_file_write_iter+0xbb/0x1d0 [ 4068.258889] > [<ffffffff81205d34>] ? __check_object_size+0x54/0x1d6 [ 4068.258891] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 4068.258892] > [<ffffffff8124603b>] blkdev_write_iter+0x8b/0x100 [ 4068.258894] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 4068.258896] > [<ffffffff8131235a>] ? import_iovec+0x3a/0xe0 [ 4068.258898] > [<ffffffff81259407>] aio_run_iocb+0x247/0x2c0 [ 4068.258900] > [<ffffffff81256586>] ? eventfd_ctx_read+0x166/0x1e0 [ 4068.258901] > [<ffffffff8121d4c0>] ? poll_select_copy_remaining+0x150/0x150 > [ 4068.258903] [<ffffffff810a6c00>] ? wake_up_q+0x80/0x80 > [ 4068.258904] [<ffffffff81227567>] ? __fget+0x77/0xb0 > [ 4068.258906] [<ffffffff81227605>] ? __fget_light+0x25/0x60 > [ 4068.258908] [<ffffffff81227653>] ? __fdget+0x13/0x20 > [ 4068.258911] [<ffffffff8125ade4>] do_io_submit+0x364/0x590 > [ 4068.258913] [<ffffffff8125b020>] SyS_io_submit+0x10/0x20 > [ 4068.258915] [<ffffffff815f8032>] > entry_SYSCALL_64_fastpath+0x1a/0xa4 [ 4068.258917] INFO: task > qemu-system-x86:903 blocked for more than 120 seconds. > [ 4068.260756] Not tainted 4.8.13-1-ARCH #1 [ 4068.262646] > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this > message. [ 4068.264530] qemu-system-x86 D ffff8802966b77a8 0 > 903 1 0x00000000 [ 4068.264533] ffff8802966b77a8 > 00ff88086ab53900 ffff880460a1c740 ffff88086ab53900 [ 4068.264535] > ffff8802966b77f8 ffff8802966b8000 ffff8804696f0ad8 ffff8802966b77e0 > [ 4068.264537] ffff8804696f0af0 ffff8804696f0000 ffff8802966b77c0 > ffffffff815f40ec [ 4068.264539] Call Trace: [ 4068.264541] > [<ffffffff815f40ec>] schedule+0x3c/0x90 [ 4068.264543] > [<ffffffff815f6669>] rwsem_down_read_failed+0xf9/0x150 > [ 4068.264545] [<ffffffff8130bb08>] > call_rwsem_down_read_failed+0x18/0x30 [ 4068.264546] > [<ffffffff815f5f07>] down_read+0x17/0x30 [ 4068.264550] > [<ffffffffa004ab9b>] cached_dev_make_request+0x63b/0xcb0 [bcache] > [ 4068.264552] [<ffffffff812cd0e2>] generic_make_request+0xf2/0x1a0 > [ 4068.264554] [<ffffffff812cd20d>] submit_bio+0x7d/0x150 > [ 4068.264556] [<ffffffff8124a1e3>] > __blockdev_direct_IO+0x31a3/0x4040 [ 4068.264558] > [<ffffffff8121d2dd>] ? poll_freewait+0x8d/0xb0 [ 4068.264560] > [<ffffffff81244520>] ? I_BDEV+0x20/0x20 [ 4068.264562] > [<ffffffff81244e43>] blkdev_direct_IO+0x43/0x50 [ 4068.264564] > [<ffffffff81179b04>] generic_file_direct_write+0xb4/0x170 > [ 4068.264566] [<ffffffff81179c7b>] > __generic_file_write_iter+0xbb/0x1d0 [ 4068.264567] > [<ffffffff81205d34>] ? __check_object_size+0x54/0x1d6 [ 4068.264569] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 4068.264571] > [<ffffffff8124603b>] blkdev_write_iter+0x8b/0x100 [ 4068.264573] > [<ffffffff81245fb0>] ? bd_acquire+0xb0/0xb0 [ 4068.264574] > [<ffffffff8131235a>] ? import_iovec+0x3a/0xe0 [ 4068.264576] > [<ffffffff81259407>] aio_run_iocb+0x247/0x2c0 [ 4068.264579] > [<ffffffff810af45c>] ? set_next_entity+0x4c/0x940 [ 4068.264581] > [<ffffffff810b41d4>] ? put_prev_entity+0xb4/0x8c0 [ 4068.264582] > [<ffffffff81227567>] ? __fget+0x77/0xb0 [ 4068.264583] > [<ffffffff81227605>] ? __fget_light+0x25/0x60 [ 4068.264585] > [<ffffffff81227653>] ? __fdget+0x13/0x20 [ 4068.264587] > [<ffffffff8125ade4>] do_io_submit+0x364/0x590 [ 4068.264589] > [<ffffffff8125b020>] SyS_io_submit+0x10/0x20 [ 4068.264590] > [<ffffffff815f8032>] entry_SYSCALL_64_fastpath+0x1a/0xa4 > -- Regards, Kai Replies to list-only preferred. -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
