Re: stalling IO regression since linux 5.12, through 5.18

From: Chris Murphy
Date: Wed Aug 17 2022 - 14:55:31 EST




On Wed, Aug 17, 2022, at 2:33 PM, Jan Kara wrote:
> On Wed 17-08-22 14:18:01, Chris Murphy wrote:
>>
>>
>> On Wed, Aug 17, 2022, at 2:15 PM, Jan Kara wrote:
>>
>> > OK, if this indeed passes then b6e68ee82585 ("blk-mq: Improve performance
>> > of non-mq IO schedulers with multiple HW queues") might be what's causing
>> > issues (although I don't know how yet...).
>>
>> I can revert it from 5.12.0 and try. Let me know which next test is preferred :)
>
> Let's try to revert this first so that we have it narrowed down what
> started causing the issues.

OK I've reverted b6e68ee82585, and removing megaraid_sas.host_tagset_enable=0, and will restart the workload...

Usually it's within 10 minutes but the newer the kernel it seems the longer it takes, or the more things I have to throw at it. The problem doesn't reproduce at all with 5.19 series unless I also run a separate dnf install, and that only triggers maybe 1 in 3 times.

--
Chris Murphy