On 5/31/19 4:27 AM, Ming Lei wrote: > Introduces parameter of 'g_host_tags' for testing hostwide tags. > > Not observe performance drop in the following test: > > 1) no 'host_tags', hw queue depth is 16, and 1 hw queue > modprobe null_blk queue_mode=2 nr_devices=4 shared_tags=1 host_tags=0 submit_queues=1 hw_queue_depth=16 > > 2) 'host_tags', global hw queue depth is 16, and 8 hw queues > modprobe null_blk queue_mode=2 nr_devices=4 shared_tags=1 host_tags=1 submit_queues=8 hw_queue_depth=16 > > 3) fio test command: > > fio --bs=4k --ioengine=libaio --iodepth=16 --filename=/dev/nullb0:/dev/nullb1:/dev/nullb2:/dev/nullb3 --direct=1 --runtime=30 --numjobs=16 --rw=randread --name=test --group_reporting --gtod_reduce=1 > > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > --- > drivers/block/null_blk_main.c | 6 ++++++ > 1 file changed, 6 insertions(+) > Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg)
