Re: [LKP] Re: [io_uring] 584b0180f0: phoronix-test-suite.fio.SequentialWrite.IO_uring.Yes.Yes.1MB.DefaultTestDirectory.mb_s -10.2% regression
From: Yin Fengwei
Date: Wed Jul 20 2022 - 23:08:59 EST
Hi Jens,
On 7/21/2022 1:24 AM, Jens Axboe wrote:
> I think this turned out to be a little bit of a goose chase. What's
> happening here is that later kernels defer the file assignment, which
> means it isn't set if a request is queued with IOSQE_ASYNC. That in
> turn, for writes, means that we don't hash it on io-wq insertion, and
> then it doesn't get serialized with other writes to that file.
Thanks a lot for the detail behavior explanation.
Regards
Yin, Fengwei