On Tue, Jun 20, 2017 at 10:16:36AM +0800, Ye Xiaolong wrote: > Hi, Christoph > > On 06/19, Christoph Hellwig wrote: > >On Mon, Jun 19, 2017 at 04:52:36PM +0800, Ye Xiaolong wrote: > >> >I've not seen a compile-time option for the MQ I/O scheduler (unlike > >> >the legacy one), so the way to change it would be to echo the name to > >> >/sys/block/<device>/queue/scheduler > >> > >> echo mq-deadline > /sys/block/<device>/queue/scheduler ? > >> > >> I'll try and post the results once I get it. > > > >Thanks! > > I've re-run the test and cat /sys/block/sda/queue/scheduler and > /sys/block/sda/queue/scheduler, and both showed "[mq-deadline] kyber none", > Does it mean they have already set as 'mq-deadline'? Yes, it seems like you're already using mq-deadline, but bfq isn't even available.