Re: [PATCHv3] io_uring: set plug tags for same file

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


On Fri, Aug 11, 2023 at 01:24:17PM -0600, Jens Axboe wrote:
>      3.51%     +2.84%  [kernel.vmlinux]  [k] io_issue_sqe
>      3.24%     +1.35%  [kernel.vmlinux]  [k] io_submit_sqes
> With the kernel without your patch, I was looking for tag flush overhead
> but didn't find much:
>      0.02%  io_uring  [kernel.vmlinux]  [k] blk_mq_free_plug_rqs
> Outside of the peak worry with the patch, do you have a workload that we
> should test this on?

Thanks for the insights! I had tested simply 4 nvme drives with 1
thread, default everything:

   ./t/io_uring /dev/nvme1n1 /dev/nvme2n1 /dev/nvme3n1 /dev/nvme4n1

Which appeared to show a very small improvement with this patch on my
test vm. I'll test more to see where the tipping point is, and also see
if there's any other ways to reduce time spent in io_issue_sqe.

[Index of Archives]     [Linux Samsung SoC]     [Linux Rockchip SoC]     [Linux Actions SoC]     [Linux for Synopsys ARC Processors]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux