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Re: mpt Serious performance issues

Now this is REALLY strange. I was wondering about why the read speed
is sometimes high (~70MB/s) and sometimes very slow (~2MB/s). So I
repeated the test utilizing

find / -exec cat {} \; > /dev/null &

to read everything from the filesystem while watching the physical
disks with my eyes and the throughput with sysstat. The findings is

-that sometimes the upper disks is 100% busy while the lower disk is
NOT being accessed at all, and the read speed is ~2MB/s
-then sometimes the adapter switches to the lower disk while the upper
disk isn´t utilised anymore, and the read speed increases to ~70MB/s
-until the adapter again switches to the upper disk which leads to the
massive decrease in speed

So what do you think about that?

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