Re: [PATCH] block: check more requests for multiple_queues in blk_attempt_plug_merge

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Mar 08, 2022 at 10:42:09PM -0800, Song Liu wrote:
> RAID arrays check/repair operations benefit a lot from merging requests.
> If we only check the previous entry for merge attempt, many merge will be
> missed. As a result, significant regression is observed for RAID check
> and repair.
> 
> Fix this by checking more than just the previous entry when
> plug->multiple_queues == true.

But this also means really significant CPU overhead for all other
workloads.

> 
> This improves the check/repair speed of a 20-HDD raid6 from 19 MB/s to
> 103 MB/s.

What driver uses multiple queues for HDDs?

Can you explain the workload submitted by a md a bit better?  I wonder
if we can easily do the right thing straight in the md driver.



[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux