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Bug #20332

closed

rados bench seq option doesn't work

Added by David Zafman almost 7 years ago. Updated over 6 years ago.

Status:
Won't Fix
Priority:
Normal
Assignee:
David Zafman
Category:
Administration/Usability
Target version:
-
% Done:

0%

Source:
Development
Tags:
Backport:
Regression:
No
Severity:
3 - minor
Reviewed:
Affected Versions:
ceph-qa-suite:
Component(RADOS):
rados tool
Pull request ID:
Crash signature (v1):
Crash signature (v2):

Description

For some reason "seq" option finishes too quickly.

$ bin/rados -p test bench 720 seq
hints = 1
  sec Cur ops   started  finished  avg MB/s  cur MB/s last lat(s)  avg lat(s)
    0       0         0         0         0         0           -           0
Total time run:       0.396085
Total reads made:     179
Read size:            4194304
Object size:          4194304
Bandwidth (MB/sec):   1807.69
Average IOPS:         451
Stddev IOPS:          0
Max IOPS:             0
Min IOPS:             2147483647
Average Latency(s):   0.0338951
Max latency(s):       0.0813923
Min latency(s):       0.00310414
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 #1

Updated by Greg Farnum almost 7 years ago

  • Project changed from Ceph to RADOS
  • Category set to Administration/Usability
  • Component(RADOS) rados tool added

Did you actually write out some data for it to read first? "seq" is just pulling back whatever was written down in the previous run (and requires he run's metadata to have been written down so it can find it!)

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 #2

Updated by Greg Farnum almost 7 years ago

  • Status changed from New to Need More Info
  • Assignee set to David Zafman
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 #3

Updated by David Zafman almost 7 years ago

  • Status changed from Need More Info to 12

I think the bug here is that the specified seconds isn't honored in the "seq" case. It probably reads every object once and then finishes. In the description I specified 720 seconds, but it did 179 reads and stopped.

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 #4

Updated by Greg Farnum almost 7 years ago

Yeah so IIRC it will stop after the specified time, but if it runs out of data that's it. I suppose it could loop? Not sure we want to make it do that though since then you're getting into even weirder caching effects. (Not that we exactly handle caching effects to begin with though, so...meh.)

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 #5

Updated by David Zafman over 6 years ago

  • Status changed from 12 to Won't Fix
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