ODA High Disk I/O Utilization and Buffer I/O error on Device Even Though Read / Write Utilization is at 0%. (Doc ID 2470505.1)

Last updated on APRIL 17, 2023

Applies to:

Symptoms

 ODA server Disk I/O utilization goes very high at regular intervals, even though read / write utilization is at 0%.

ODA environment:X4-2 VM

** Out Put of : iostat -dx /dev/sdby 2 shown below.
===============================

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 1.00 1.00 1024.00 24.00 524.00 6.37 2198.50 500.00 100.00

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 1.50 0.00 1032.00 0.00 688.00 5.12 655.67 600.67 90.10

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 7.00 10.00 3112.00 168.00 192.94 12.06 952.68 54.94 93.40

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 1.50 0.00 1016.00 0.00 677.33 3.66 481.33 665.67 99.85

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 6.50 4.50 696.00 72.00 69.82 1.59 425.73 19.32 21.25

Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util
sdby 0.00 0.00 3.50 2.00 2544.00 32.00 468.36 1.67 23.91 87.36 48.05

Changes

Cause

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