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?
