Re: [RFC 3/3] io_uring: try to batch poll request completion

Hao Xu
2021-09-22T17:00:51Z

在 2021/9/22 下午8:34, Xiaoguang Wang 写道:
> For an echo-server based on io_uring's IORING_POLL_ADD_MULTI feature,
> only poll request are completed in task work, normal read/write
> requests are issued when user app sees cqes on corresponding poll
> requests, and they will mostly read/write data successfully, which
> don't need task work. So at least for echo-server model, batching
> poll request completion properly will give benefits.
>
> Currently don't find any appropriate place to store batched poll
> requests, put them in struct io_submit_state temporarily, which I
> think it'll need rework in future.
>
> Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
We may need flush completion when io_submit_end as well, there may be
situations where pure poll reqs are sparse. For instance, users may
just use pure poll to do accept, and fast poll for read/write,
send/recv, latency for pure poll reqs may amplify.