>> The test hardware is: >> Kunpeng-920, HW-SAS3508+(MG04ACA400N * 2), RAID0. > Please also provide performance numbers for a single hard disk and with > no RAID controller between the host and the hard disk. > Thanks, > Bart. Hi, Yesterday I found another server without raid controller to test a same HDD, but the performance(The data is not stable, so I tested it many times) wasn't what I expected. Also I tested a SSD with raid contriller on a previous Kunpeng server and the performance improved, but that's not always the case with SSDs on other servers. This may indicate that the raid controller plays an important role in this, so I'm not sure if this patch really has the desired effect. Thanks, Wang. The test hardware is: Hygon C86, MG04ACA400N The test command is: fio -ioengine=psync -lockmem=1G -buffered=0 -time_based=1 -direct=1 -iodepth=1 -thread -bs=512B -size=110g -numjobs=32 -runtime=300 -group_reporting -name=read -filename=/dev/sdc -ioscheduler=mq-deadline -rw=read[,write,rw] The following is the test data: origin/master: read iops: 15463 write iops: 5949 rw iops: 574,576 nr_sched_batch = 1: read iops: 15082 write iops: 6283 rw iops: 783,786 nr_sched_batch = 1, use deadline_head_request: read iops: 15368 write iops: 6575 rw iops: 907,906 The test hardware is: Kunpeng-920, HW-SAS3508 + Samsung SSD 780, RAID0. The test command is: fio -ioengine=psync -lockmem=1G -buffered=0 -time_based=1 -direct=1 -iodepth=1 -thread -bs=512B -size=110g -numjobs=16 -runtime=300 -group_reporting -name=read -filename=/dev/sda -ioscheduler=mq-deadline -rw=read[,write,rw] The following is the test data: origin/master: read iops: 115399 write iops: 136801 rw iops: 58082,58084 nr_sched_batch = 1, use deadline_head_request: read iops: 136473 write iops: 184646 rw iops: 56460,56454