On Fri, Nov 22, 2019 at 08:16:30PM +0100, Andrea Vai wrote: > Il giorno dom, 10/11/2019 alle 06.28 +0800, Ming Lei ha scritto: > > Another thing we could try is to use 'none' via the following > > command: > > > > echo none > /sys/block/sdh/queue/scheduler #suppose 'sdh' points > > to the usb storage disk > > > > Because USB storage HBA is single hw queue, which depth is 1. This > > way > > should change to dispatch IO in the order of bio submission. > > > > Andrea, could you switch io scheduler to none and update us if > > difference > > can be made? > > Using the new kernel, there is indeed a difference because the time to > copy a file is 1800 seconds with [mq-deadline], and 340 seconds with > [none]. But that is still far away from the old kernel, which performs > the copy of the same file in 76 seconds. Please post the log of 'lsusb -v', and I will try to make a patch for addressing the issue. thanks, Ming
