On 25/09/14 09:35, Vincent Guittot wrote:

On 24 September 2014 19:48, Dietmar Eggemann [off-list ref] wrote:

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On 23/09/14 17:08, Vincent Guittot wrote:

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This review (by PeterZ) during v5 of your patch-set recommended some
renaming (e.g. s/group_has_free_capacity/group_has_capacity and
s/group_out_of_capacity/group_no_capacity as well as reordering of the
parameters which I agree with:

https://lkml.org/lkml/2014/9/11/706

Ah... you're right, these changes have passed through my seance of renaming

What about the ordering of the function parameters in
group_has_capacity, group_is_overloaded and group_type group_classify?

All the existing *load balance* related functions in fair.c seem to
follow this (struct lb_env *env, struct sd_lb_stats *sds, struct
sched_group *group, struct sg_lb_stats *sgs) order.

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-/*

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-       if (sgs->group_capacity_factor > sgs->sum_nr_running)
-               sgs->group_has_free_capacity = 1;
+       sgs->group_type = group_classify(group, sgs, env);
+
+       sgs->group_out_of_capacity = group_is_overloaded(sgs, env);

In case sgs->group_type is group_overloaded you could set
sgs->group_out_of_capacity to 1 without calling group_is_overloaded again.

I prefer to keep sgs->group_out_of_capacity = group_is_overloaded(sgs,
env) and use it in group_classify in case of future changes in the
classification order

Ok, but than group_is_overloaded is called twice at the end of
update_sg_lb_stats with exactly the same result. Looks weird in my traces.

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