Re: [PATCH BUGFIX] block, bfq: deschedule empty bfq_queues not referred by any process

From: Paolo Valente
Date: Thu Nov 14 2019 - 04:22:08 EST




> Il giorno 13 nov 2019, alle ore 23:46, Jens Axboe <axboe@xxxxxxxxx> ha scritto:
>
> On 11/13/19 10:42 AM, Paolo Valente wrote:
>>
>>
>>> Il giorno 13 nov 2019, alle ore 16:01, Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx> ha scritto:
>>>
>>> On 13.11.2019 15:25, Oleksandr Natalenko wrote:
>>>> I didn't try to switch schedulers, but what I see now is once the
>>>> system is able to boot with BFQ, the I/O can still hang on I/O burst
>>>> (which for me happens to happen during VM reboot).
>>>> This may also not hang forever, but just slow down considerably. I've
>>>> noticed this inside a KVM VM, not on a real HW.
>>>
>>> Possible call traces:
>>
>> Ok, you may have given me enough information, thank you very much.
>>
>> Could you please apply the attached (compressed) patch on top of my
>> offending patch? For review purposes, here is the simple change:
>
> FWIW, I dropped the previous patch.
>

Thanks. I'm sending a V2.

Thanks,
Paolo

> --
> Jens Axboe