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I want to know the relationship of the await, r_await and w_await columns in the output from iostat -x.

Below is an example output of an iostat I/O statistics.

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           7.55    0.01    5.70    7.31    0.00   79.44

Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
sdq               0.35    14.58   60.61  112.75   789.04  1172.86    22.63     1.45    8.39   17.76    3.35   1.19  20.65
sda               0.01     0.66   65.84   20.44  9450.37  2838.27   284.86     0.04    0.49   18.31   25.28   4.68  40.39
Scott - Слава Україні
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user991704
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1 Answers1

6

  • await is the average time (in milliseconds) for I/O requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

  • r_await is the average time (in milliseconds) for read requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

  • w_await is the average time (in milliseconds) for write requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

    You can go through the iostat manual for more information regarding the other outputs.

angelofdev
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