LP #838939: pt-diskstats reports wrong amount of writes/second

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**Reported in Launchpad by Daniel Nichter last update 01-02-2012 16:16:52

Imported from http://code.google.com/p/aspersa/issues/detail?id=137:

The problem I have is that I get different results when looking at iostat and diskstats (5 second intervals):

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util
sdc 0.00 277.56 104.01 415.83 936.27 5574.35 468.14 2787.17 12.52 6.34 12.18 1.24 64.57

#ts device rd_s rd_avkb rd_mb_s rd_mrg rd_cnc rd_rt wr_s wr_avkb wr_mb_s wr_mrg wr_cnc wr_rt busy in_prg
{1} sdc1 133.2 10.1 0.7 0% 0.9 6.6 841.5 13.9 5.7 42% 12.3 14.7 87% 0
{1} sdc1 154.8 7.9 0.6 0% 0.7 4.3 590.4 9.1 2.6 12% 9.1 15.4 71% 0

The amount of writes/s that iostat is measuring is about 5600 while diskstats only mentions 600.
/proc/diskstats tells me iostat is correct

raw diskstats output:
TS 1301045501.005860000 2011-03-25 05:31:41
8 33 sdc1 1572537676 2369344 3687151364 1575056414 2541895139 1708184481 3991989096 121136333 1 982122453 1798311795
TS 1301045506.010994000 2011-03-25 05:31:46
8 33 sdc1 1572538262 2369344 3687156316 1575060551 2541899787 1708186654 3992043720 121207970 4 982126782 1798388127
TS 1301045511.016149000 2011-03-25 05:31:51
8 33 sdc1 1572538898 2369344 3687161404 1575064096 2541903848 1708186950 3992078608 121272417 1 982130754 1798455962
TS 1301045516.021280000 2011-03-25 05:31:56

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lpjirasync January 24, 2018 at 2:51 PM

**Comment from Launchpad by: Daniel Nichter on: 01-02-2012 15:36:54

Changing to Invalid since it's not that we're not going to fix it, but rather "it" (the bug) has been invalidated by the fact that you rewrote the tool.

lpjirasync January 24, 2018 at 2:51 PM

**Comment from Launchpad by: Brian Fraser on: 31-01-2012 20:41:26

Marking this as "Won't fix" as I can't seem able to reproduce it, and the tool itself was rewritten from scratch. Daniel, if you can reproduce it again, please let me know and/or reopen this?

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Created January 24, 2018 at 2:51 PM
Updated February 4, 2018 at 12:06 AM
Resolved January 24, 2018 at 2:51 PM