Did you wait for several measurements from iostat, say over 30s? Utilization may be spikey.

"%util" is a measurement of how hard your disk drive is working, on a scale from 0-100. What's in that column?

Pasting the output of a 30s measurement would be enlightening.

In reply to Re^4: how to split huge file reading into multiple threads by onelesd
in thread how to split huge file reading into multiple threads by sagarika

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