Re: Bug? CQE.res = -EAGAIN with nvme multipath driver

[Jens Axboe <axboe@kernel.dk>]

On 1/9/25 11:09 AM, Haeuptle, Michael wrote:
> Hey Jens, sorry for the late response.
> 
> I was unable to reproduce the issue with your branch. However, I
> didn't even hit the spot where same_thread_group check was removed.

Might be a driver side issue too on the nvme front, if it no longer hits
the retry path as much.

> We backported your changes to 6.1.119 and we did see that our original
> issue is fixed with your patches.
> 
> It seems to me that io_uring performance increased quite a bit in the
> latest kernel, judging from fio queue utilization of my workload.
> Maybe that's why I'm not hitting the place where same_thread_group was
> removed.

We do try and improve performance all the time, but most likely this is
caused by the same effect that reduces the reissue attempts as well.

> Your patch didn't cause any regression after 1d testing in my
> NVMF/RDMA & multipath setup. So, I think it would be good to get this
> patch on main.

Queued up, thanks for testing.

-- 
Jens Axboe