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Subject: Re: [PATCH v6 2/2] sched: update the rq->avg_idle when a task is
 moved to an idle CPU
From: Dietmar Eggemann <dietmar.eggemann@arm.com>
To: Shijie Huang <shijie@amperemail.onmicrosoft.com>,
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On 17.12.25 17:15, Dietmar Eggemann wrote:
> On 15.12.25 10:35, Shijie Huang wrote:
>>
>> On 12/12/2025 22:22, Dietmar Eggemann wrote:

[...]

> I think Vincent is right by saying the update_rq_avg_idle() should be
> put into put_prev_task_idle() instead.
> 
> Still waiting for the DCPerf Mediawiki test results to see if this
> change fixes my 'rq->avg_idle being too big' issue.

Turns out the patch didn't fix this issue. Still seeing a huge number of
sched_balance_newidle() calls in which the system is (1) overloaded and
(2) this_rq->avg_idle >= sd->max_newidle_lb_cost so that there is no
early bailout and no task is pulled at the end. Must be something else ...