16.04 with 4.15.0-36-generic kernel: system freezes with several worker threads blocked/hanging in BTRFS...
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16.04 with 4.15.0-36-generic kernel: system freezes with several worker threads blocked/hanging in BTRFS module
ubuntu hang out with this message :blocked for more than 120 secondsroot file system mounts as read only after some timeVMware kernel module update error in ubuntu 16.04 with kernel 4.4.0-53-genericError to load module btusb with kernel 4.10.0-20-genericUbuntu 17.04 Problemssystem freezes and kernel panicks ubuntu 16.04“echo 0 > /proc/sys/kernel/hung_task_timeout_secs” disables this messageRecover corrupt USB: visible in lsblk and lsusb, nowhere elsecannot access ssh and proxmox web GUI, cuase linux kernel panic issueAfter most recent kernel update (4.15.0-44-generic) my tablet freezes whenever plugged into docking station
We are Ubuntu shop running Xenial (16.04) with Linux kernel 4.15.0-36-generic. We recently migrated our application code from Ubuntu 14.04/linux kernel 4.4.0-23. We are experiencing some system hang issues (described below) with 16.04 environment, that we did not encounter with 14.04 and the 4.4 kernel.
Our secondary storage (256GB Micron SSD) is mounted on /dev/sdb with BTRFS filesystem. We are experiencing a system hang during large file copy/modify operations with following messages like this on the system console tty:
> [147778.018904] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147778.026992] Tainted: P OE
> 4.15.0-36-generic #1 [147778.033914] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.042918] INFO: task auditd:1138 blocked for more than 120
> seconds. [147778.050218] Tainted: P OE
> 4.15.0-36-generic #1 [147778.057116] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.066125] INFO: task cron:24933 blocked for more than 120
> seconds. [147778.073317] Tainted: P OE
> 4.15.0-36-generic #1 [147778.080225] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.089664] INFO: task cron:24934 blocked for more than 120
> seconds. [147778.096866] Tainted: P OE
> 4.15.0-36-generic #1 [147778.103764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.113159] INFO: task cron:24935 blocked for more than 120
> seconds. [147778.120360] Tainted: P OE
> 4.15.0-36-generic #1 [147778.127267] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147898.850483] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147898.858569] Tainted: P OE
> 4.15.0-36-generic #1 [147898.865490] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
This happens sometimes during shutdown (reboot) or during system bringup. We do have several file operations going on in background during these times. We were able to collect "dmesg" output from an ssh session that was still alive:
[ 1034.371130] perf: interrupt took too long (14517 > 14503), lowering kernel.perf_event_max_sample_rate to 13750
[ 1157.254266] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.290278] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.312982] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.332657] BTRFS info (device sdb3): disk space caching is enabled
[ 1248.012861] ata1.00: Enabling discard_zeroes_data
[ 1248.020748] sda: sda1
sda1: <solaris: [s0] sda5 [s2] sda6 [s8] sda7 >
[ 1257.996027] BTRFS info (device sdb3): qgroup scan completed (inconsistency flag cleared)
[ 1451.046237] INFO: task kworker/u24:0:5 blocked for more than 120 seconds.
[ 1451.054217] Tainted: P OE 4.15.0-36-generic #1
[ 1451.061152] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.069963] kworker/u24:0 D 0 5 2 0x80000000
[ 1451.070199] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.070257] Call Trace:
[ 1451.070312] __schedule+0x3d6/0x8b0
[ 1451.070332] ? blk_rq_map_sg+0x13c/0x550
[ 1451.070336] schedule+0x36/0x80
[ 1451.070366] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.070381] ? wait_woken+0x80/0x80
[ 1451.070400] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.070417] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.070421] ? update_load_avg+0x5e0/0x700
[ 1451.070442] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.070465] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.070488] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070510] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070513] ? _cond_resched+0x1a/0x50
[ 1451.070515] ? _cond_resched+0x1a/0x50
[ 1451.070535] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.070557] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.070578] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.070601] ? end_compressed_bio_write+0x102/0x140 [btrfs]
[ 1451.070622] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.070644] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.070667] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.070672] process_one_work+0x14d/0x410
[ 1451.070675] worker_thread+0x4b/0x460
[ 1451.070679] kthread+0x105/0x140
[ 1451.070680] ? process_one_work+0x410/0x410
[ 1451.070683] ? kthread_destroy_worker+0x50/0x50
[ 1451.070686] ret_from_fork+0x35/0x40
[ 1451.070733] INFO: task kworker/u24:1:101 blocked for more than 120 seconds.
[ 1451.078559] Tainted: P OE 4.15.0-36-generic #1
[ 1451.085426] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.094228] kworker/u24:1 D 0 101 2 0x80000000
[ 1451.094275] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.094278] Call Trace:
[ 1451.094282] __schedule+0x3d6/0x8b0
[ 1451.094285] schedule+0x36/0x80
[ 1451.094307] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.094310] ? wait_woken+0x80/0x80
[ 1451.094327] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.094343] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.094363] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.094384] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.094407] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094428] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094431] ? _cond_resched+0x1a/0x50
[ 1451.094434] ? _cond_resched+0x1a/0x50
[ 1451.094455] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.094475] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.094495] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.094499] ? __switch_to_asm+0x40/0x70
[ 1451.094503] ? __switch_to_asm+0x34/0x70
[ 1451.094505] ? __switch_to_asm+0x40/0x70
[ 1451.094524] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.094546] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.094569] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.094571] process_one_work+0x14d/0x410
[ 1451.094575] worker_thread+0x4b/0x460
[ 1451.094578] kthread+0x105/0x140
[ 1451.094580] ? process_one_work+0x410/0x410
[ 1451.094582] ? kthread_destroy_worker+0x50/0x50
[ 1451.094585] ret_from_fork+0x35/0x40
[ 1451.094603] INFO: task kworker/u24:2:271 blocked for more than 120 seconds.
[ 1451.102453] Tainted: P OE 4.15.0-36-generic #1
[ 1451.109330] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.118138] kworker/u24:2 D 0 271 2 0x80000000
[ 1451.118165] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.118173] Call Trace:
[ 1451.118180] __schedule+0x3d6/0x8b0
[ 1451.118183] schedule+0x36/0x80
[ 1451.118205] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.118215] ? wait_woken+0x80/0x80
[ 1451.118231] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.118252] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.118273] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.118296] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.118319] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118342] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118346] ? _cond_resched+0x1a/0x50
[ 1451.118368] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.118389] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.118412] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.118435] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.118459] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.118484] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.118487] process_one_work+0x14d/0x410
[ 1451.118490] worker_thread+0x4b/0x460
[ 1451.118493] kthread+0x105/0x140
[ 1451.118495] ? process_one_work+0x410/0x410
[ 1451.118498] ? kthread_destroy_worker+0x50/0x50
[ 1451.118501] ret_from_fork+0x35/0x40
The following is our /etc/fstab entries that shows the various BTRFS mount options that we have already tried one at a time:
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 / btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@/netvisor-1 0 1
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /home btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@home 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /var/nvOS/log btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@var_nvOS_log 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /.rootbe btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@ 0 1
Does this indicate that we are hitting some known issues with BTRFS filesystem deadlock that may have been fixed in later kernel versions? If so, how should we go about obtaining those fixes in our current kernel? Upgrading the kernel is not an option for us at this time. Are there any other BTRFS mount options or any other system tunable parameters we could try to circumvent this hang issues.
Thanks in advance.
kernel mount filesystem btrfs
asked 10 mins ago
Prasanna Prasanna
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We are Ubuntu shop running Xenial (16.04) with Linux kernel 4.15.0-36-generic. We recently migrated our application code from Ubuntu 14.04/linux kernel 4.4.0-23. We are experiencing some system hang issues (described below) with 16.04 environment, that we did not encounter with 14.04 and the 4.4 kernel.
Our secondary storage (256GB Micron SSD) is mounted on /dev/sdb with BTRFS filesystem. We are experiencing a system hang during large file copy/modify operations with following messages like this on the system console tty:
> [147778.018904] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147778.026992] Tainted: P OE
> 4.15.0-36-generic #1 [147778.033914] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.042918] INFO: task auditd:1138 blocked for more than 120
> seconds. [147778.050218] Tainted: P OE
> 4.15.0-36-generic #1 [147778.057116] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.066125] INFO: task cron:24933 blocked for more than 120
> seconds. [147778.073317] Tainted: P OE
> 4.15.0-36-generic #1 [147778.080225] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.089664] INFO: task cron:24934 blocked for more than 120
> seconds. [147778.096866] Tainted: P OE
> 4.15.0-36-generic #1 [147778.103764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.113159] INFO: task cron:24935 blocked for more than 120
> seconds. [147778.120360] Tainted: P OE
> 4.15.0-36-generic #1 [147778.127267] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147898.850483] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147898.858569] Tainted: P OE
> 4.15.0-36-generic #1 [147898.865490] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
This happens sometimes during shutdown (reboot) or during system bringup. We do have several file operations going on in background during these times. We were able to collect "dmesg" output from an ssh session that was still alive:
[ 1034.371130] perf: interrupt took too long (14517 > 14503), lowering kernel.perf_event_max_sample_rate to 13750
[ 1157.254266] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.290278] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.312982] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.332657] BTRFS info (device sdb3): disk space caching is enabled
[ 1248.012861] ata1.00: Enabling discard_zeroes_data
[ 1248.020748] sda: sda1
sda1: <solaris: [s0] sda5 [s2] sda6 [s8] sda7 >
[ 1257.996027] BTRFS info (device sdb3): qgroup scan completed (inconsistency flag cleared)
[ 1451.046237] INFO: task kworker/u24:0:5 blocked for more than 120 seconds.
[ 1451.054217] Tainted: P OE 4.15.0-36-generic #1
[ 1451.061152] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.069963] kworker/u24:0 D 0 5 2 0x80000000
[ 1451.070199] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.070257] Call Trace:
[ 1451.070312] __schedule+0x3d6/0x8b0
[ 1451.070332] ? blk_rq_map_sg+0x13c/0x550
[ 1451.070336] schedule+0x36/0x80
[ 1451.070366] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.070381] ? wait_woken+0x80/0x80
[ 1451.070400] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.070417] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.070421] ? update_load_avg+0x5e0/0x700
[ 1451.070442] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.070465] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.070488] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070510] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070513] ? _cond_resched+0x1a/0x50
[ 1451.070515] ? _cond_resched+0x1a/0x50
[ 1451.070535] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.070557] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.070578] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.070601] ? end_compressed_bio_write+0x102/0x140 [btrfs]
[ 1451.070622] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.070644] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.070667] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.070672] process_one_work+0x14d/0x410
[ 1451.070675] worker_thread+0x4b/0x460
[ 1451.070679] kthread+0x105/0x140
[ 1451.070680] ? process_one_work+0x410/0x410
[ 1451.070683] ? kthread_destroy_worker+0x50/0x50
[ 1451.070686] ret_from_fork+0x35/0x40
[ 1451.070733] INFO: task kworker/u24:1:101 blocked for more than 120 seconds.
[ 1451.078559] Tainted: P OE 4.15.0-36-generic #1
[ 1451.085426] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.094228] kworker/u24:1 D 0 101 2 0x80000000
[ 1451.094275] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.094278] Call Trace:
[ 1451.094282] __schedule+0x3d6/0x8b0
[ 1451.094285] schedule+0x36/0x80
[ 1451.094307] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.094310] ? wait_woken+0x80/0x80
[ 1451.094327] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.094343] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.094363] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.094384] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.094407] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094428] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094431] ? _cond_resched+0x1a/0x50
[ 1451.094434] ? _cond_resched+0x1a/0x50
[ 1451.094455] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.094475] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.094495] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.094499] ? __switch_to_asm+0x40/0x70
[ 1451.094503] ? __switch_to_asm+0x34/0x70
[ 1451.094505] ? __switch_to_asm+0x40/0x70
[ 1451.094524] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.094546] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.094569] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.094571] process_one_work+0x14d/0x410
[ 1451.094575] worker_thread+0x4b/0x460
[ 1451.094578] kthread+0x105/0x140
[ 1451.094580] ? process_one_work+0x410/0x410
[ 1451.094582] ? kthread_destroy_worker+0x50/0x50
[ 1451.094585] ret_from_fork+0x35/0x40
[ 1451.094603] INFO: task kworker/u24:2:271 blocked for more than 120 seconds.
[ 1451.102453] Tainted: P OE 4.15.0-36-generic #1
[ 1451.109330] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.118138] kworker/u24:2 D 0 271 2 0x80000000
[ 1451.118165] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.118173] Call Trace:
[ 1451.118180] __schedule+0x3d6/0x8b0
[ 1451.118183] schedule+0x36/0x80
[ 1451.118205] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.118215] ? wait_woken+0x80/0x80
[ 1451.118231] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.118252] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.118273] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.118296] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.118319] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118342] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118346] ? _cond_resched+0x1a/0x50
[ 1451.118368] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.118389] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.118412] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.118435] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.118459] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.118484] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.118487] process_one_work+0x14d/0x410
[ 1451.118490] worker_thread+0x4b/0x460
[ 1451.118493] kthread+0x105/0x140
[ 1451.118495] ? process_one_work+0x410/0x410
[ 1451.118498] ? kthread_destroy_worker+0x50/0x50
[ 1451.118501] ret_from_fork+0x35/0x40
The following is our /etc/fstab entries that shows the various BTRFS mount options that we have already tried one at a time:
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 / btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@/netvisor-1 0 1
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /home btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@home 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /var/nvOS/log btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@var_nvOS_log 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /.rootbe btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@ 0 1
Does this indicate that we are hitting some known issues with BTRFS filesystem deadlock that may have been fixed in later kernel versions? If so, how should we go about obtaining those fixes in our current kernel? Upgrading the kernel is not an option for us at this time. Are there any other BTRFS mount options or any other system tunable parameters we could try to circumvent this hang issues.
Thanks in advance.
kernel mount filesystem btrfs
asked 10 mins ago
Prasanna Prasanna
1
New contributor
Prasanna is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
We are Ubuntu shop running Xenial (16.04) with Linux kernel 4.15.0-36-generic. We recently migrated our application code from Ubuntu 14.04/linux kernel 4.4.0-23. We are experiencing some system hang issues (described below) with 16.04 environment, that we did not encounter with 14.04 and the 4.4 kernel.
Our secondary storage (256GB Micron SSD) is mounted on /dev/sdb with BTRFS filesystem. We are experiencing a system hang during large file copy/modify operations with following messages like this on the system console tty:
> [147778.018904] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147778.026992] Tainted: P OE
> 4.15.0-36-generic #1 [147778.033914] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.042918] INFO: task auditd:1138 blocked for more than 120
> seconds. [147778.050218] Tainted: P OE
> 4.15.0-36-generic #1 [147778.057116] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.066125] INFO: task cron:24933 blocked for more than 120
> seconds. [147778.073317] Tainted: P OE
> 4.15.0-36-generic #1 [147778.080225] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.089664] INFO: task cron:24934 blocked for more than 120
> seconds. [147778.096866] Tainted: P OE
> 4.15.0-36-generic #1 [147778.103764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.113159] INFO: task cron:24935 blocked for more than 120
> seconds. [147778.120360] Tainted: P OE
> 4.15.0-36-generic #1 [147778.127267] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147898.850483] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147898.858569] Tainted: P OE
> 4.15.0-36-generic #1 [147898.865490] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
This happens sometimes during shutdown (reboot) or during system bringup. We do have several file operations going on in background during these times. We were able to collect "dmesg" output from an ssh session that was still alive:
[ 1034.371130] perf: interrupt took too long (14517 > 14503), lowering kernel.perf_event_max_sample_rate to 13750
[ 1157.254266] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.290278] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.312982] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.332657] BTRFS info (device sdb3): disk space caching is enabled
[ 1248.012861] ata1.00: Enabling discard_zeroes_data
[ 1248.020748] sda: sda1
sda1: <solaris: [s0] sda5 [s2] sda6 [s8] sda7 >
[ 1257.996027] BTRFS info (device sdb3): qgroup scan completed (inconsistency flag cleared)
[ 1451.046237] INFO: task kworker/u24:0:5 blocked for more than 120 seconds.
[ 1451.054217] Tainted: P OE 4.15.0-36-generic #1
[ 1451.061152] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.069963] kworker/u24:0 D 0 5 2 0x80000000
[ 1451.070199] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.070257] Call Trace:
[ 1451.070312] __schedule+0x3d6/0x8b0
[ 1451.070332] ? blk_rq_map_sg+0x13c/0x550
[ 1451.070336] schedule+0x36/0x80
[ 1451.070366] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.070381] ? wait_woken+0x80/0x80
[ 1451.070400] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.070417] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.070421] ? update_load_avg+0x5e0/0x700
[ 1451.070442] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.070465] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.070488] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070510] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070513] ? _cond_resched+0x1a/0x50
[ 1451.070515] ? _cond_resched+0x1a/0x50
[ 1451.070535] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.070557] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.070578] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.070601] ? end_compressed_bio_write+0x102/0x140 [btrfs]
[ 1451.070622] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.070644] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.070667] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.070672] process_one_work+0x14d/0x410
[ 1451.070675] worker_thread+0x4b/0x460
[ 1451.070679] kthread+0x105/0x140
[ 1451.070680] ? process_one_work+0x410/0x410
[ 1451.070683] ? kthread_destroy_worker+0x50/0x50
[ 1451.070686] ret_from_fork+0x35/0x40
[ 1451.070733] INFO: task kworker/u24:1:101 blocked for more than 120 seconds.
[ 1451.078559] Tainted: P OE 4.15.0-36-generic #1
[ 1451.085426] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.094228] kworker/u24:1 D 0 101 2 0x80000000
[ 1451.094275] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.094278] Call Trace:
[ 1451.094282] __schedule+0x3d6/0x8b0
[ 1451.094285] schedule+0x36/0x80
[ 1451.094307] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.094310] ? wait_woken+0x80/0x80
[ 1451.094327] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.094343] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.094363] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.094384] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.094407] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094428] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094431] ? _cond_resched+0x1a/0x50
[ 1451.094434] ? _cond_resched+0x1a/0x50
[ 1451.094455] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.094475] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.094495] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.094499] ? __switch_to_asm+0x40/0x70
[ 1451.094503] ? __switch_to_asm+0x34/0x70
[ 1451.094505] ? __switch_to_asm+0x40/0x70
[ 1451.094524] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.094546] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.094569] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.094571] process_one_work+0x14d/0x410
[ 1451.094575] worker_thread+0x4b/0x460
[ 1451.094578] kthread+0x105/0x140
[ 1451.094580] ? process_one_work+0x410/0x410
[ 1451.094582] ? kthread_destroy_worker+0x50/0x50
[ 1451.094585] ret_from_fork+0x35/0x40
[ 1451.094603] INFO: task kworker/u24:2:271 blocked for more than 120 seconds.
[ 1451.102453] Tainted: P OE 4.15.0-36-generic #1
[ 1451.109330] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.118138] kworker/u24:2 D 0 271 2 0x80000000
[ 1451.118165] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.118173] Call Trace:
[ 1451.118180] __schedule+0x3d6/0x8b0
[ 1451.118183] schedule+0x36/0x80
[ 1451.118205] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.118215] ? wait_woken+0x80/0x80
[ 1451.118231] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.118252] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.118273] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.118296] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.118319] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118342] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118346] ? _cond_resched+0x1a/0x50
[ 1451.118368] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.118389] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.118412] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.118435] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.118459] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.118484] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.118487] process_one_work+0x14d/0x410
[ 1451.118490] worker_thread+0x4b/0x460
[ 1451.118493] kthread+0x105/0x140
[ 1451.118495] ? process_one_work+0x410/0x410
[ 1451.118498] ? kthread_destroy_worker+0x50/0x50
[ 1451.118501] ret_from_fork+0x35/0x40
The following is our /etc/fstab entries that shows the various BTRFS mount options that we have already tried one at a time:
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 / btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@/netvisor-1 0 1
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /home btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@home 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /var/nvOS/log btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@var_nvOS_log 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /.rootbe btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@ 0 1
Does this indicate that we are hitting some known issues with BTRFS filesystem deadlock that may have been fixed in later kernel versions? If so, how should we go about obtaining those fixes in our current kernel? Upgrading the kernel is not an option for us at this time. Are there any other BTRFS mount options or any other system tunable parameters we could try to circumvent this hang issues.
Thanks in advance.
kernel mount filesystem btrfs
asked 10 mins ago
Prasanna Prasanna
1
New contributor
Prasanna is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
We are Ubuntu shop running Xenial (16.04) with Linux kernel 4.15.0-36-generic. We recently migrated our application code from Ubuntu 14.04/linux kernel 4.4.0-23. We are experiencing some system hang issues (described below) with 16.04 environment, that we did not encounter with 14.04 and the 4.4 kernel.
Our secondary storage (256GB Micron SSD) is mounted on /dev/sdb with BTRFS filesystem. We are experiencing a system hang during large file copy/modify operations with following messages like this on the system console tty:
> [147778.018904] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147778.026992] Tainted: P OE
> 4.15.0-36-generic #1 [147778.033914] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.042918] INFO: task auditd:1138 blocked for more than 120
> seconds. [147778.050218] Tainted: P OE
> 4.15.0-36-generic #1 [147778.057116] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.066125] INFO: task cron:24933 blocked for more than 120
> seconds. [147778.073317] Tainted: P OE
> 4.15.0-36-generic #1 [147778.080225] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.089664] INFO: task cron:24934 blocked for more than 120
> seconds. [147778.096866] Tainted: P OE
> 4.15.0-36-generic #1 [147778.103764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147778.113159] INFO: task cron:24935 blocked for more than 120
> seconds. [147778.120360] Tainted: P OE
> 4.15.0-36-generic #1 [147778.127267] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> [147898.850483] INFO: task btrfs-transacti:440 blocked for more than
> 120 seconds. [147898.858569] Tainted: P OE
> 4.15.0-36-generic #1 [147898.865490] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
This happens sometimes during shutdown (reboot) or during system bringup. We do have several file operations going on in background during these times. We were able to collect "dmesg" output from an ssh session that was still alive:
[ 1034.371130] perf: interrupt took too long (14517 > 14503), lowering kernel.perf_event_max_sample_rate to 13750
[ 1157.254266] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.290278] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.312982] BTRFS info (device sdb3): disk space caching is enabled
[ 1157.332657] BTRFS info (device sdb3): disk space caching is enabled
[ 1248.012861] ata1.00: Enabling discard_zeroes_data
[ 1248.020748] sda: sda1
sda1: <solaris: [s0] sda5 [s2] sda6 [s8] sda7 >
[ 1257.996027] BTRFS info (device sdb3): qgroup scan completed (inconsistency flag cleared)
[ 1451.046237] INFO: task kworker/u24:0:5 blocked for more than 120 seconds.
[ 1451.054217] Tainted: P OE 4.15.0-36-generic #1
[ 1451.061152] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.069963] kworker/u24:0 D 0 5 2 0x80000000
[ 1451.070199] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.070257] Call Trace:
[ 1451.070312] __schedule+0x3d6/0x8b0
[ 1451.070332] ? blk_rq_map_sg+0x13c/0x550
[ 1451.070336] schedule+0x36/0x80
[ 1451.070366] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.070381] ? wait_woken+0x80/0x80
[ 1451.070400] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.070417] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.070421] ? update_load_avg+0x5e0/0x700
[ 1451.070442] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.070465] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.070488] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070510] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.070513] ? _cond_resched+0x1a/0x50
[ 1451.070515] ? _cond_resched+0x1a/0x50
[ 1451.070535] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.070557] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.070578] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.070601] ? end_compressed_bio_write+0x102/0x140 [btrfs]
[ 1451.070622] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.070644] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.070667] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.070672] process_one_work+0x14d/0x410
[ 1451.070675] worker_thread+0x4b/0x460
[ 1451.070679] kthread+0x105/0x140
[ 1451.070680] ? process_one_work+0x410/0x410
[ 1451.070683] ? kthread_destroy_worker+0x50/0x50
[ 1451.070686] ret_from_fork+0x35/0x40
[ 1451.070733] INFO: task kworker/u24:1:101 blocked for more than 120 seconds.
[ 1451.078559] Tainted: P OE 4.15.0-36-generic #1
[ 1451.085426] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.094228] kworker/u24:1 D 0 101 2 0x80000000
[ 1451.094275] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.094278] Call Trace:
[ 1451.094282] __schedule+0x3d6/0x8b0
[ 1451.094285] schedule+0x36/0x80
[ 1451.094307] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.094310] ? wait_woken+0x80/0x80
[ 1451.094327] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.094343] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.094363] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.094384] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.094407] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094428] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.094431] ? _cond_resched+0x1a/0x50
[ 1451.094434] ? _cond_resched+0x1a/0x50
[ 1451.094455] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.094475] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.094495] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.094499] ? __switch_to_asm+0x40/0x70
[ 1451.094503] ? __switch_to_asm+0x34/0x70
[ 1451.094505] ? __switch_to_asm+0x40/0x70
[ 1451.094524] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.094546] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.094569] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.094571] process_one_work+0x14d/0x410
[ 1451.094575] worker_thread+0x4b/0x460
[ 1451.094578] kthread+0x105/0x140
[ 1451.094580] ? process_one_work+0x410/0x410
[ 1451.094582] ? kthread_destroy_worker+0x50/0x50
[ 1451.094585] ret_from_fork+0x35/0x40
[ 1451.094603] INFO: task kworker/u24:2:271 blocked for more than 120 seconds.
[ 1451.102453] Tainted: P OE 4.15.0-36-generic #1
[ 1451.109330] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1451.118138] kworker/u24:2 D 0 271 2 0x80000000
[ 1451.118165] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
[ 1451.118173] Call Trace:
[ 1451.118180] __schedule+0x3d6/0x8b0
[ 1451.118183] schedule+0x36/0x80
[ 1451.118205] btrfs_tree_lock+0xef/0x210 [btrfs]
[ 1451.118215] ? wait_woken+0x80/0x80
[ 1451.118231] btrfs_lock_root_node+0x34/0x50 [btrfs]
[ 1451.118252] btrfs_search_slot+0x914/0x9d0 [btrfs]
[ 1451.118273] btrfs_lookup_file_extent+0x49/0x60 [btrfs]
[ 1451.118296] __btrfs_drop_extents+0x19e/0xe60 [btrfs]
[ 1451.118319] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118342] ? __set_extent_bit+0x466/0x5a0 [btrfs]
[ 1451.118346] ? _cond_resched+0x1a/0x50
[ 1451.118368] insert_reserved_file_extent.constprop.68+0x90/0x2d0 [btrfs]
[ 1451.118389] ? start_transaction+0x9b/0x440 [btrfs]
[ 1451.118412] btrfs_finish_ordered_io+0x300/0x720 [btrfs]
[ 1451.118435] finish_ordered_fn+0x15/0x20 [btrfs]
[ 1451.118459] normal_work_helper+0xcb/0x320 [btrfs]
[ 1451.118484] btrfs_endio_write_helper+0x12/0x20 [btrfs]
[ 1451.118487] process_one_work+0x14d/0x410
[ 1451.118490] worker_thread+0x4b/0x460
[ 1451.118493] kthread+0x105/0x140
[ 1451.118495] ? process_one_work+0x410/0x410
[ 1451.118498] ? kthread_destroy_worker+0x50/0x50
[ 1451.118501] ret_from_fork+0x35/0x40
The following is our /etc/fstab entries that shows the various BTRFS mount options that we have already tried one at a time:
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 / btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@/netvisor-1 0 1
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /home btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@home 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /var/nvOS/log btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@var_nvOS_log 0 2
UUID=3a899529-c5e4-42ae-a4ea-7b645f9bcb59 /.rootbe btrfs defaults,autodefrag,thread_pool=4,compress=lzo,noatime,subvol=@ 0 1
Does this indicate that we are hitting some known issues with BTRFS filesystem deadlock that may have been fixed in later kernel versions? If so, how should we go about obtaining those fixes in our current kernel? Upgrading the kernel is not an option for us at this time. Are there any other BTRFS mount options or any other system tunable parameters we could try to circumvent this hang issues.
Thanks in advance.
kernel mount filesystem btrfs
kernel mount filesystem btrfs
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