summaryrefslogtreecommitdiff
path: root/block/blk-wbt.c
diff options
context:
space:
mode:
authorBart Van Assche <bvanassche@acm.org>2021-06-17 17:44:56 -0700
committerJens Axboe <axboe@kernel.dk>2021-06-21 15:03:41 -0600
commitfb926032b3209300f9dc454a36b8299582ae545c (patch)
tree411a2d4709a8caa68aa74b4c7bcd354065bc0b64 /block/blk-wbt.c
parent08a9ad8bf607388d768a341957d53eae64250c2d (diff)
block/mq-deadline: Prioritize high-priority requests
While one or more requests with a certain I/O priority are pending, do not dispatch lower priority requests. Dispatch lower priority requests anyway after the "aging" time has expired. This patch has been tested as follows: modprobe scsi_debug ndelay=1000000 max_queue=16 && sd='' && while [ -z "$sd" ]; do sd=/dev/$(basename /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/*) done && echo $((100*1000)) > /sys/block/$sd/queue/iosched/aging_expire && cd /sys/fs/cgroup/blkio/ && echo $$ >cgroup.procs && echo restrict-to-be >blkio.prio.class && mkdir -p hipri && cd hipri && echo none-to-rt >blkio.prio.class && { max-iops -a1 -d32 -j1 -e mq-deadline $sd >& ~/low-pri.txt & } && echo $$ >cgroup.procs && max-iops -a1 -d32 -j1 -e mq-deadline $sd >& ~/hi-pri.txt Result: * 11000 IOPS for the high-priority job * 40 IOPS for the low-priority job If the aging expiry time is changed from 100s into 0, the IOPS results change into 6712 and 6796 IOPS. The max-iops script is a script that runs fio with the following arguments: --bs=4K --gtod_reduce=1 --ioengine=libaio --ioscheduler=${arg_e} --runtime=60 --norandommap --rw=read --thread --buffered=0 --numjobs=${arg_j} --iodepth=${arg_d} --iodepth_batch_submit=${arg_a} --iodepth_batch_complete=$((arg_d / 2)) --name=${positional_argument_1} --filename=${positional_argument_1} Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Cc: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210618004456.7280-17-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-wbt.c')
0 files changed, 0 insertions, 0 deletions