On Tue, Oct 07, 2014 at 02:13:36PM +0200, Vincent Guittot wrote:

+static inline bool
+group_has_capacity(struct lb_env *env, struct sg_lb_stats *sgs)
 {
+	if ((sgs->group_capacity * 100) >
+			(sgs->group_usage * env->sd->imbalance_pct))
+		return true;

Why the imb_pct there? We're looking for 100% utilization, not 130 or
whatnot, right?

+	if (sgs->sum_nr_running < sgs->group_weight)
+		return true;

With the code as it stands, this is the cheaper test (no mults) so why
is it second?

+	return false;
+}
 
+static inline bool
+group_is_overloaded(struct lb_env *env, struct sg_lb_stats *sgs)
+{
+	if (sgs->sum_nr_running <= sgs->group_weight)
+		return false;
+
+	if ((sgs->group_capacity * 100) <
+			(sgs->group_usage * env->sd->imbalance_pct))
+		return true;
 
+	return false;
 }

Same thing here wrt imb_pct