Re: [PATCH -next 0/3] md/raid10: reduce lock contention for io

[Yu Kuai <yukuai1@huaweicloud.com>]

Hi!

在 2022/08/29 21:40, Guoqing Jiang 写道:
> 
> 
> On 8/29/22 9:14 PM, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> patch 1 is a small problem found by code review.
>> patch 2 avoid holding resync_lock in fast path.
>> patch 3 avoid holding lock in wake_up() in fast path.
>>
>> Test environment:
>>
>> Architecture: aarch64
>> Cpu: Huawei KUNPENG 920, there are four numa nodes
>>
>> Raid10 initialize:
>> mdadm --create /dev/md0 --level 10 --bitmap none --raid-devices 4 
>> /dev/nvme0n1 /dev/nvme1n1 /dev/nvme2n1 /dev/nvme3n1
>>
>> Test cmd:
>> fio -name=0 -ioengine=libaio -direct=1 -group_reporting=1 
>> -randseed=2022 -rwmixread=70 -refill_buffers -filename=/dev/md0 
>> -numjobs=16 -runtime=60s -bs=4k -iodepth=256 -rw=randread
>>
>> Test result:
>> before this patchset:    2.9 GiB/s
>> after this patchset:    6.6 Gib/s
> 
> Impressive! Pls try mdadm test suites too to avoid regression.
> 
>> Please noted that in kunpeng-920, memory access latency is very bad
>> accross nodes compare to local node, and in other architecture
>> performance improvement might not be significant.
> 
> By any chance can someone try with x64?

I tried to test with Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz,

before this patchset: 7.0 GiB/s
after this patchset : 9.3 GiB/s

Thanks,
Kuai
> 
> Thanks,
> Guoqing
> .
>