* Martin Roehricht <[EMAIL PROTECTED]> wrote: > On 08/02/2007 05:19 PM, Ingo Molnar wrote: > >* Martin Roehricht <[EMAIL PROTECTED]> wrote: > > > >>That's fine with me, that within the same priority-queue any task can > >>be chosen. But assume two tasks with highly different priorities, such > >>as 105 and 135 are scheduled on the same processor and one of them is > >>now to be migrated -- shouldn't be the queue with task P=105 > >>considered first for migration by this code? Both tasks would use > >>different queues with their own linked lists, right? > > > >yes. What makes you believe that the lower priority one (prio 135) is > >chosen? [ as i said before, that will only be chosen if all tasks in the > >higher-priority queue (prio 105) are either already running on a CPU or > >have recently run so that the cache-hot logic skips them. ] > > This believe is primarily based on my observations of multiple > benchmark runs and also on your statement earlier: »in the SMP > migration code, the 'old scheduler' indeed picks the lowest priority > one«.
oh, sorry, that was meant to be the 'highest priority one' :-/ so i think you got it all right, i just typoed that first sentence. Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/