Re: [RFC PATCH 0/4] cgroup aware workqueues

From: Bandan Das
Date: Mon Apr 04 2016 - 13:00:22 EST


...
>> There have been discussions about this in the past and iirc, most people
> agree
>> about not going the byos* route. But I am still all for such a proposal
> and if
>> it's good/clean enough, I think we can definitely tear down what we have
> and
>> throw it away! The I/O scheduling part is intrusive enough that even the
> current
>> code base has to be changed quite a bit.
>
> The "byos" route seems more promising with respect to possible performance
> gains, but it will definitely add complexity, and I cannot say if the
> added complexity will be worth performance improvements.
>
> Meanwhile, I'd suggest we better understand what causes regression with
> your current patches and maybe then we'll be smarter to get to the right
> direction. :)
>

Agreed, let's try to understand the cause of the "underperformance" with wqs.
I disabled WQ_CGROUPS that effectively disables my changes and I can still
consistently reproduce the lower numbers.

>> *byos = bring your own scheduling ;)
>>
>> > Thanks.
>
> --
> Sincerely yours,
> Mike.
>
> [1] https://lwn.net/Articles/650857/