I have started read-scan the disk using:
smartctl -t select,10-11 -t afterselect,on -t pending,45 /dev/sda
It seems, however, it kills the disk performance. I had expected that the read-scan would (just like the tests) be suspended when there was disk activity.
I had also expected the read scan (like the tests) would run without load on the server, but according to
iostat -x -d 1 it seems read-test goes through the controller.
Is this normal? Can I suspend the read scan when the disk is active (e.g. only run read scan if idle for 500 ms)?