On 14/09/14 12:41, 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.
My understanding is that uArch scaling of capacacity_orig (therefore of capacity too) is done by calling arch_scale_cpu_capacity and frequency scaling for capacity is done by calling arch_scale_freq_capacity in update_cpu_capacity. I understand that this patch-set does not provide an implementation of arch_scale_freq_capacity though.
The uArch and frequency scaling of load & utilization will be added later. I know that Morten is currently working on a 'uArch and frequency invariant load & utilization tracking' patch-set.
Although I don't know exactly what you mean by DVFS accounting and remove cpufreq from the capacity here.
-- Dietmar
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/