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1===================2Switching Scheduler3===================4 5Each io queue has a set of io scheduler tunables associated with it. These6tunables control how the io scheduler works. You can find these entries7in::8 9 /sys/block/<device>/queue/iosched10 11assuming that you have sysfs mounted on /sys. If you don't have sysfs mounted,12you can do so by typing::13 14 # mount none /sys -t sysfs15 16It is possible to change the IO scheduler for a given block device on17the fly to select one of mq-deadline, none, bfq, or kyber schedulers -18which can improve that device's throughput.19 20To set a specific scheduler, simply do this::21 22 echo SCHEDNAME > /sys/block/DEV/queue/scheduler23 24where SCHEDNAME is the name of a defined IO scheduler, and DEV is the25device name (hda, hdb, sga, or whatever you happen to have).26 27The list of defined schedulers can be found by simply doing28a "cat /sys/block/DEV/queue/scheduler" - the list of valid names29will be displayed, with the currently selected scheduler in brackets::30 31 # cat /sys/block/sda/queue/scheduler32 [mq-deadline] kyber bfq none33 # echo none >/sys/block/sda/queue/scheduler34 # cat /sys/block/sda/queue/scheduler35 [none] mq-deadline kyber bfq36