Uploaded image for project: 'Lustre'
  1. Lustre
  2. LU-17853

Negative value reported in req_waittime mdt

XMLWordPrintable

    • Icon: Bug Bug
    • Resolution: Fixed
    • Icon: Minor Minor
    • Lustre 2.16.0
    • Lustre 2.14.0
    • 3
    • 9223372036854775807 

      ldlm.services.ldlm_canceld.stats=
snapshot_time             1714662722.986857642 secs.nsecs
req_waittime              101358239600 samples [usecs] -36 1855805 5530720965329 21563670935443407
req_qdepth                101358239600 samples [reqs] 0 1164 1893537183 7828947261
req_active                101358239600 samples [reqs] 1 23 152657095033 281200017837
req_timeout               101358239600 samples [secs] 1 218 6892805470378 468801155450006
reqbuf_avail              210996467581 samples [bufs] 0 155 13398749465845 850967459690601
ldlm_cancel               101358239600 samples [usecs] 1 211241571 1436530054018 108103493490971286

      This doesn't appear to be a math error like LU-9683, but possibly caused by NTP.

      ptlrpc uses ktime_get_real() for timing events where other modules use ktime_get() for timing.

      ktime_get_real() "can jump backwards due to a leap second update, NTP adjustment settimeofday() operation from user space."

            fdilger Fred Dilger
            utopiabound Nathaniel Clark
            Votes:
            0 Vote for this issue
            Watchers:
            6 Start watching this issue

              Created:
              Updated:
              Resolved: