iostat

# iostat -x 2 100
Linux 3.10.0-693.2.2.el7.x86_64 (bj-prod-be-api-0-115)         09/22/2018         _x86_64_        (4 CPU)
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           6.48    0.00    1.85    0.47    0.00   91.19
Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
vda               0.27     0.89    8.76    3.08   922.13    17.34   158.68     0.26   22.29   27.37    7.82   0.75   0.89
vdb               0.00     0.06    2.71    1.47   215.15   225.03   210.55     0.18   43.61    4.59  115.65   0.68   0.28
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           7.06    0.00    6.46   63.04    0.00   23.44
Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
vda             107.00     0.00  964.50   63.50 113098.00   266.00   220.55    26.43   25.42   26.84    3.76   1.01 103.70
vdb               0.00     0.00  281.50    1.00 17796.00     4.00   126.02     0.81    2.85    2.85    3.50   0.36  10.15
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           3.26    0.00    5.14   49.75    0.00   41.85
Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
vda              15.42    19.40  901.00   65.67 106175.12   350.25   220.40    22.92   23.22   24.61    4.23   1.00  96.72
vdb               0.00     0.00  221.39    1.00 17488.56     5.72   157.33     0.83    3.71    3.72    1.00   0.31   6.82

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