David,
Hope you are doing fine, two weeks ago I saw a similar behavior in a 21400 cluster running R80.20 but with CPU interrupts, they went from 10 to billions in seconds. No increases in the CPU load overall.
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I opened a TAC case for this and they told that it was cosmetic only, then I went to /proc/interrupts and it was fine.
My guess is that when CPUs are under load CPView may lead to some funny numbers.
I recommend you to use iostat and iostats -dx
There are more flags to play with, just look online and you will find many helpful examples.
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Regards,
____________
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