Re: [RFC PATCH v2] sched/fair: select idle cpu from idle cpumask in sched domain

[Vincent Guittot]

Hi Tim

On Thu, 24 Sep 2020 at 18:37, Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> wrote:
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>
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> On 9/22/20 12:14 AM, Vincent Guittot wrote:
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> >>
> >>>>
> >>>> And a quick test with hackbench on my octo cores arm64 gives for 12
>
> Vincent,
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> Is it octo (=10) or octa (=8) cores on a single socket for your system?

it's a 8 cores and the cores are splitted in 2 cache domains

> The L2 is per core or there are multiple L2s shared among groups of cores?
>
> Wonder if placing the threads within a L2 or not within
> an L2 could cause differences seen with Aubrey's test.

I haven't checked recently but the 2 tasks involved in sched pipe run
on CPUs which belong to the same cache domain

Vincent

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> Tim
>