Re: [patch v5 01/15] sched: set initial value for runnable avg ofsched entities.

From: Alex Shi
Date: Mon Feb 18 2013 - 04:15:53 EST


On 02/18/2013 04:28 PM, Joonsoo Kim wrote:
> On Mon, Feb 18, 2013 at 01:07:28PM +0800, Alex Shi wrote:
>> > We need initialize the se.avg.{decay_count, load_avg_contrib} to zero
>> > after a new task forked.
>> > Otherwise random values of above variables cause mess when do new task
> I think that these are not random values. In arch_dup_task_struct(),
> we do '*dst = *src', so, these values come from parent process. If we use
> these value appropriately, we can anticipate child process' load easily.
> So to initialize the load_avg_contrib to zero is not good idea for me.

Um, for a new forked task, calling them random value is appropriate,
since uncertain value of decay_count make random behaviour in
enqueue_entity_load_avg().
And many comments said new forked task need not follow parent's
utilisations, like what's you claimed for exec.

--
Thanks Alex
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