Re: [PATCH for-5.16 v3 0/8] task work optimization

[Hao Xu <haoxu@linux.alibaba.com>]

在 2021/10/27 下午10:02, Hao Xu 写道:
> Tested this patchset by manually replace __io_queue_sqe() in
> io_queue_sqe() by io_req_task_queue() to construct 'heavy' task works.
> Then test with fio:
> 
> ioengine=io_uring
> sqpoll=1
> thread=1
> bs=4k
> direct=1
> rw=randread
> time_based=1
> runtime=600
> randrepeat=0
> group_reporting=1
> filename=/dev/nvme0n1
> 
> 2/8 set unlimited priority_task_list, 8/8 set a limitation of
> 1/3 * (len_prority_list + len_normal_list), data below:
>     depth     no 8/8   include 8/8      before this patchset
>      1        7.05         7.82              7.10
>      2        8.47         8.48              8.60
>      4        10.42        9.99              10.42
>      8        13.78        13.13             13.22
>      16       27.41        27.92             24.33
>      32       49.40        46.16             53.08
>      64       102.53       105.68            103.36
>      128      196.98       202.76            205.61
>      256      372.99       375.61            414.88
>      512      747.23       763.95            791.30
>      1024     1472.59      1527.46           1538.72
>      2048     3153.49      3129.22           3329.01
>      4096     6387.86      5899.74           6682.54
>      8192     12150.25     12433.59          12774.14
>      16384    23085.58     24342.84          26044.71
> 
The data in the previous v2 version seems not right, I may miss
something at that time.
> It seems 2/8 is better, haven't tried other choices other than 1/3,
> still put 8/8 here for people's further thoughts.
> 
> Hao Xu (8):
>    io-wq: add helper to merge two wq_lists
>    io_uring: add a priority tw list for irq completion work
>    io_uring: add helper for task work execution code
>    io_uring: split io_req_complete_post() and add a helper
>    io_uring: move up io_put_kbuf() and io_put_rw_kbuf()
>    io_uring: add nr_ctx to record the number of ctx in a task
>    io_uring: batch completion in prior_task_list
>    io_uring: add limited number of TWs to priority task list
> 
>   fs/io-wq.h    |  21 +++++++
>   fs/io_uring.c | 168 +++++++++++++++++++++++++++++++++++---------------
>   2 files changed, 138 insertions(+), 51 deletions(-)
>