Re: [Bug] fio hang when running multiple job io_uring/hipri over nvme

[Ming Lei]

On Thu, Jun 17, 2021 at 10:56:53AM -0600, Jens Axboe wrote:
> On 6/17/21 10:48 AM, Jens Axboe wrote:
> > On 6/17/21 5:17 AM, Ming Lei wrote:
> >> Hello,
> >>
> >> fio hangs when running the test[1], and doesn't observe this issue
> >> when running a
> >> such single job test.
> >>
> >> v5.12 is good, both v5.13-rc3 and the latest v5.13-rc6 are bad.
> >>
> >>
> >> [1] fio test script and log
> >> + fio --bs=4k --ioengine=io_uring --fixedbufs --registerfiles --hipri
> >> --iodepth=64 --iodepth_batch_submit=16
> >> --iodepth_batch_complete_min=16 --filename=/dev/nvme0n1 --direct=1
> >> --runtime=20 --numjobs=4 --rw=randread
> >> --name=test --group_reporting
> >>
> >> test: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T)
> >> 4096B-4096B, ioengine=io_uring, iodepth=64
> >> ...
> >> fio-3.25
> >> Starting 4 processes
> >> fio: filehash.c:64: __lookup_file_hash: Assertion `f->fd != -1' failed.
> >> fio: pid=1122, got signal=6
> >> ^Cbs: 3 (f=0): [f(1),r(1),K(1),r(1)][63.6%][eta 00m:20s]
> > 
> > Funky, would it be possible to bisect this? I'll see if I can reproduce.
> 
> Actually, this looks like a fio bug, that assert is a bit too trigger
> happy. Current -git should work, please test and see if things work.
> I believe it's just kernel timing that causes this, not a kernel issue.

Yeah, current -git does work, thanks the fix!

-- 
Ming