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Subject: Re: [RFC 00/60] Coscheduling for Linux
To:     "=?UTF-8?Q?Jan_H._Sch=c3=b6nherr?=" <jschoenh@amazon.de>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
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From:   Subhra Mazumdar <subhra.mazumdar@oracle.com>
Message-ID: <cb7ce9a8-2274-913a-62ff-7a84de9505f1@oracle.com>
Date:   Thu, 27 Sep 2018 11:12:33 -0700
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On 09/24/2018 08:43 AM, Jan H. Schönherr wrote:
> On 09/19/2018 11:53 PM, Subhra Mazumdar wrote:
>> Can we have a more generic interface, like specifying a set of task ids
>> to be co-scheduled with a particular level rather than tying this with
>> cgroups? KVMs may not always run with cgroups and there might be other
>> use cases where we might want co-scheduling that doesn't relate to
>> cgroups.
> Currently: no.
>
> At this point the implementation is tightly coupled to the cpu cgroup
> controller. This *might* change, if the task group optimizations mentioned
> in other parts of this e-mail thread are done, as I think, that it would
> decouple the various mechanisms.
>
> That said, what if you were able to disable the "group-based fairness"
> aspect of the cpu cgroup controller? Then you would be able to control
> just the coscheduling aspects on their own. Would that satisfy the use
> case you have in mind?
>
> Regards
> Jan
Yes that will suffice the use case. We wish to experiment at some point
with co-scheduling of certain workers threads in DB parallel query and see
if there is any benefit

Thanks,
Subhra