Messages in this thread | | | Subject | Re: [PATCH] blk-mq: allow hardware queue to get more tag while sharing a tag set | From | Bart Van Assche <> | Date | Mon, 2 Aug 2021 09:17:31 -0700 |
| |
On 8/2/21 6:34 AM, yukuai (C) wrote: > I run a test on both null_blk and nvme, results show that there are no > performance degradation: > > test platform: x86 > test cpu: 2 nodes, total 72 > test scheduler: none > test device: null_blk / nvme > > test cmd: fio -filename=/dev/xxx -name=test -ioengine=libaio -direct=1 > -numjobs=72 -iodepth=16 -bs=4k -rw=write -offset_increment=1G > -cpus_allowed=0:71 -cpus_allowed_policy=split -group_reporting > -runtime=120 > > test results: iops > 1) null_blk before this patch: 280k > 2) null_blk after this patch: 282k > 3) nvme before this patch: 378k > 4) nvme after this patch: 384k
Please use io_uring for performance tests.
The null_blk numbers seem way too low to me. If I run a null_blk performance test inside a VM with 6 CPU cores (Xeon W-2135 CPU) I see about 6 million IOPS for synchronous I/O and about 4.4 million IOPS when using libaio. The options I used and that are not in the above command line are: --thread --gtod_reduce=1 --ioscheduler=none.
Thanks,
Bart.
| |