[LU-4427] performance-sanity test_6: mdsrate hung (sys_mknod)

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Affects Version/s: Lustre 2.5.1, Lustre 2.4.3, Lustre 2.8.0
• Labels: zfs
• Environment: Lustre Build: http://build.whamcloud.com/job/lustre-b2_5/5/; FSTYPE=zfs
• Severity: 3
• Assignee: Nathaniel Clark
• Reporter: Jian Yu

Description

performance-sanity test_6 hung as follows on client:

13:08:35:Lustre: DEBUG MARKER: ===== mdsrate-lookup-10dirs.sh Test preparation: creating 10 dirs with 26778 files.
13:08:35:INFO: task mdsrate:19365 blocked for more than 120 seconds.
13:08:35:"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
13:08:35:mdsrate       D 0000000000000001     0 19365  19361 0x00000080
13:08:35: ffff88005eba1ac8 0000000000000082 0000000000000000 ffff88006e406800
13:08:35: ffff88005eba1a88 ffffffffa0681629 ffff88007a0aee00 0000000000000003
13:08:35: ffff88006dfd2638 ffff88005eba1fd8 000000000000fb88 ffff88006dfd2638
13:08:35:Call Trace:
13:08:35: [<ffffffffa0681629>] ? __ptlrpc_request_bufs_pack+0x349/0x3c0 [ptlrpc]
13:08:35: [<ffffffff8150f78e>] __mutex_lock_slowpath+0x13e/0x180
13:08:35: [<ffffffff8150f62b>] mutex_lock+0x2b/0x50
13:08:35: [<ffffffffa084a8dc>] mdc_reint+0x3c/0x3b0 [mdc]
13:08:35: [<ffffffffa084beae>] mdc_create+0x20e/0x780 [mdc]
13:08:35: [<ffffffffa0ae6196>] lmv_create+0x316/0x700 [lmv]
13:08:35: [<ffffffffa09dbf46>] ll_new_node+0x176/0x640 [lustre]
13:08:35: [<ffffffffa09dc578>] ll_mknod_generic+0x168/0x280 [lustre]
13:08:35: [<ffffffff8118e0e3>] ? generic_permission+0x23/0xb0
13:08:35: [<ffffffffa09e2ef1>] ll_create_nd+0x971/0xe80 [lustre]
13:08:35: [<ffffffff8118e4c2>] ? __lookup_hash+0x102/0x160
13:08:35: [<ffffffff8118fbd4>] vfs_create+0xb4/0xe0
13:08:35: [<ffffffff81192800>] sys_mknodat+0x280/0x2a0
13:08:35: [<ffffffff8100bb8e>] ? apic_timer_interrupt+0xe/0x20
13:08:35: [<ffffffff8119283a>] sys_mknod+0x1a/0x20
13:08:35: [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b

Maloo report: https://maloo.whamcloud.com/test_sets/fc281616-73c4-11e3-b4ff-52540035b04c

Issue Links

• is duplicated by: LU-4408 parallel-scale test statahead hung
• is related to: LU-3786 performance-sanity test_6: mkdir hung (sys_mkdir)

Comments

[Nathaniel Clark]

The most recent failure of this type is from 2015-03-24 (all other perf-sanity/6 timeouts are LU-3786)
https://testing.hpdd.intel.com/test_sets/d817106c-d325-11e4-a357-5254006e85c2

[Alex Zhuravlev]

I can't find any problem in the report above. can it be that ZFS is just making progress too slow?

[Jian Yu]

Does this still happen?

By searching on Maloo, I found the latest performance-sanity test 6 time out failures were all LU-3786.

[James A Simmons]

Does this still happen?

[Sarah Liu]

another instance:
https://testing.hpdd.intel.com/test_sets/5ccde712-1251-11e5-bec9-5254006e85c2

[Jian Yu]

FYI, by searching on Maloo, I found the failure did not occur on master branch. I also tried to reproduce the failure on master build #2820 but failed to hit the issue.

Here are the test reports on master build #2820:

performance-sanity:
https://testing.hpdd.intel.com/test_sets/b60591f8-9d6d-11e4-9d48-5254006e85c2 (ldiskfs)
https://testing.hpdd.intel.com/test_sets/b915d632-9d6d-11e4-9d48-5254006e85c2 (ldiskfs)
https://testing.hpdd.intel.com/test_sets/34af27f2-9fe5-11e4-a43c-5254006e85c2 (zfs)
https://testing.hpdd.intel.com/test_sets/98bf8674-9fe5-11e4-a43c-5254006e85c2 (zfs)

parallel-scale:
https://testing.hpdd.intel.com/test_sets/bc82d59a-9d6d-11e4-9d48-5254006e85c2 (ldiskfs)
https://testing.hpdd.intel.com/test_sets/c5ccc930-9d6d-11e4-9d48-5254006e85c2 (ldiskfs)
https://testing.hpdd.intel.com/test_sets/7af16a0c-9fc4-11e4-a450-5254006e85c2 (zfs)
https://testing.hpdd.intel.com/test_sets/a98eeeb6-9fc4-11e4-a450-5254006e85c2 (zfs)
https://testing.hpdd.intel.com/test_sets/bffa1554-9fc4-11e4-a450-5254006e85c2 (zfs)
https://testing.hpdd.intel.com/test_sets/f702fb8e-9ef6-11e4-a23e-5254006e85c2 (zfs)
https://testing.hpdd.intel.com/test_sets/fd7dc124-9ef6-11e4-a23e-5254006e85c2 (zfs)

[Nathaniel Clark]

performance-sanity/6 hangs seems to fall into two catagories.
1) performance-sanity/5 fails (LU-4428 or LU-5146) then mdsrate hangs (this bug)
2) test_5 passes and mkdir hangs (LU-3786)

[Jian Yu]

Lustre Build: http://build.whamcloud.com/job/lustre-b2_5/61/
FSTYPE=zfs

The same failure occurred: https://maloo.whamcloud.com/test_sets/50a6f7f0-ebe5-11e3-82b2-52540035b04c

[Peter Jones]

Nathaniel

Could you please look into this one?

Thanks

Peter

[Jian Yu]

Lustre build: http://build.whamcloud.com/job/lustre-b2_5/47/
FSTYPE=zfs

The same failure occurred:
https://maloo.whamcloud.com/test_sets/99e3e576-cb70-11e3-95c9-52540035b04c