z_rd_int is blocked

[storcium]

System information

Type	Version/Name
Distribution Name

Ubuntu 16.04

Distribution Version |
Linux Kernel |

4.14.24-custom (ZFS built in)

Architecture |
ZFS Version |

v0.7.0-356_g639b189

SPL Version |

v0.7.0-30_g3673d03

Describe the problem you're observing

Load average goes very high (150 and higher) and the following errors are logged:

Apr 28 22:36:56 issapl4 kernel: [209279.502130] INFO: task z_rd_int_0:1678 blocked for more than 120 seconds.
Apr 28 22:36:56 issapl4 kernel: [209279.502222] Not tainted 4.14.24-custom #7
Apr 28 22:36:56 issapl4 kernel: [209279.502303] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Apr 28 22:36:56 issapl4 kernel: [209279.502393] z_rd_int_0 D 0 1678 2 0x80000000
Apr 28 22:36:56 issapl4 kernel: [209279.502396] Call Trace:
Apr 28 22:36:56 issapl4 kernel: [209279.502405] ? __schedule+0x3d2/0x8b0
Apr 28 22:36:56 issapl4 kernel: [209279.502407] schedule+0x32/0x80
Apr 28 22:36:56 issapl4 kernel: [209279.502410] schedule_preempt_disabled+0xa/0x10
Apr 28 22:36:56 issapl4 kernel: [209279.502413] __mutex_lock.isra.2+0x2b1/0x4e0
Apr 28 22:36:56 issapl4 kernel: [209279.502418] ? vdev_queue_io_done+0x43/0x230
Apr 28 22:36:56 issapl4 kernel: [209279.502420] vdev_queue_io_done+0x43/0x230
Apr 28 22:36:56 issapl4 kernel: [209279.502423] zio_vdev_io_done+0xca/0x1e0
Apr 28 22:36:56 issapl4 kernel: [209279.502425] zio_execute+0x87/0xe0
Apr 28 22:36:56 issapl4 kernel: [209279.502429] taskq_thread+0x299/0x4a0
Apr 28 22:36:56 issapl4 kernel: [209279.502433] ? wake_up_q+0x60/0x60
Apr 28 22:36:56 issapl4 kernel: [209279.502436] ? zio_reexecute+0x400/0x400
Apr 28 22:36:56 issapl4 kernel: [209279.502438] kthread+0xff/0x140
Apr 28 22:36:56 issapl4 kernel: [209279.502441] ? taskq_thread_should_stop+0x70/0x70
Apr 28 22:36:56 issapl4 kernel: [209279.502443] ? kthread_create_on_node+0x70/0x70
Apr 28 22:36:56 issapl4 kernel: [209279.502446] ret_from_fork+0x35/0x40
Apr 28 22:36:56 issapl4 kernel: [209279.502449] INFO: task z_rd_int_1:1679 blocked for more than 120 seconds.
Apr 28 22:36:56 issapl4 kernel: [209279.502536] Not tainted 4.14.24-custom #7

Describe how to reproduce the problem

This has happened on two systems already, during high but not too high of IO operational load.

Include any warning/errors/backtraces from the system logs

[stale]

This issue has been automatically marked as "stale" because it has not had any activity for a while. It will be closed in 90 days if no further activity occurs. Thank you for your contributions.