On Sun, Sep 14, 2014 at 09:41:56PM +0200, Peter Zijlstra wrote:
On Thu, Sep 11, 2014 at 07:26:48PM +0200, Vincent Guittot wrote:
On 11 September 2014 18:15, Peter Zijlstra peterz@infradead.org wrote:
On Tue, Aug 26, 2014 at 01:06:54PM +0200, Vincent Guittot wrote:
+static inline int group_has_free_capacity(struct sg_lb_stats *sgs,
struct lb_env *env)
{
if ((sgs->group_capacity_orig * 100) >
(sgs->group_utilization * env->sd->imbalance_pct))
return 1;
if (sgs->sum_nr_running < sgs->group_weight)
return 1;
return 0;
+}
+static inline int group_is_overloaded(struct sg_lb_stats *sgs,
struct lb_env *env)
+{
if (sgs->sum_nr_running <= sgs->group_weight)
return 0;
if ((sgs->group_capacity_orig * 100) <
(sgs->group_utilization * env->sd->imbalance_pct))
return 1;
return 0;
}
I'm confused about the utilization vs capacity_orig. I see how we should
1st point is that I should compare utilization vs capacity and not capacity_orig. I should have replaced capacity_orig by capacity in the functions above when i move the utilization statistic from rq->avg.runnable_avg_sum to cfs.usage_load_avg. rq->avg.runnable_avg_sum was measuring all activity on the cpu whereas cfs.usage_load_avg integrates only cfs tasks
With this change, we don't need sgs->group_capacity_orig anymore but only sgs->group_capacity. So sgs->group_capacity_orig can be removed as it's no more used in the code as sg_capacity_factor has been removed
Yes, but.. so I suppose we need to add DVFS accounting and remove cpufreq from the capacity thing. Otherwise I don't see it make sense.
That is to say, please also explain these details in the changelog, and preferably also in a XXX/FIXME/TODO comment near wherever so we don't forget about it.