[LU-1800] Job Stats shows statahead thread

• Status: Resolved
• Project: Lustre
• Affects Version/s: Lustre 2.3.0, Lustre 2.4.0, Lustre 2.10.1
• Type: Bug
• Priority: Major
• Reporter: Andreas Dilger
• Assignee: Ben Evans (Inactive)
• Resolution: Fixed
• Severity: 3

Description

I was just looking at lctl get_param mdt.*.job_stats to see what it showed, now that test-framework.sh enables it by default. It appears that the "ll_sa_<pid>" threads are showing up as a separate job for every "ls" being run, instead of only "ls.<uid>" as I would expect.

- job_id:          ll_sa_14097_0
  snapshot_time:   1346211655
  getattr:         { samples:           5, unit:  reqs }

Is it possible to do something like is done for IO, to store the jobid into the inode for the statahead, or pass the JobID on to the statahead thread, so that it doesn't send "ll_sa_*" as the process name?

Comments

[Andreas Dilger]

This is still an issue with 2.10.1 at least.

Ben, is there any chance you could look into this? I think passing on the "parent" JobID from the process running "ls" to the statahead thread would be best. It might be possible to pass environment variables to new threads via kthread_create() at launch time, but I'm not positive.

[Ben Evans (Inactive)]

I'll take a look, is there a good reproducer I can use to see the problem?

[Andreas Dilger]

For reproducer, just enable jobstats on the client (e.g. lctl set_param jobid_var=procname_uid), run "ls -l" on a directory, and check jobstats on the server(s).

[Ben Evans (Inactive)]

Fixed in LU-10698