26 Mar
2013
26 Mar
'13
1 p.m.
On 26 March 2013 13:37, Peter Zijlstra peterz@infradead.org wrote:
On Fri, 2013-03-22 at 13:25 +0100, Vincent Guittot wrote:
+static bool is_light_task(struct task_struct *p) +{
/* A light task runs less than 20% in average */return ((p->se.avg.runnable_avg_sum * 5) <(p->se.avg.runnable_avg_period));+}
OK, so we have a 'problem' here, we initialize runnable_avg_* to 0, but we want to 'assume' a fresh task is fully 'loaded'. IIRC Alex ran into this as well.
Hi Peter,
The packing small tasks is only applied at wake up and not during fork or exec so the runnable_avg_* should have been initialized. As you mentionned, we assume that a fresh task is fully loaded and let the default scheduler behavior to select a target CPU
Vincent
PJT, do you have any sane solution for this, I forgot what the result of the last discussion was -- was there any?