Messages in this thread | | | Subject | Re: [SHED] Questions. | From | Robert Love <> | Date | Sun, 31 Aug 2003 15:51:18 -0400 |
| |
On Sun, 2003-08-31 at 15:31, Ian Kumlien wrote:
> Since they would have a high pri still, and preempt is there... it > should be back on the cpu pretty quick.
Ah, but no! You assume we do not have an expired list and round robin scheduling.
Once a task exhausts its timeslice, it cannot run until all other tasks exhaust their timeslice. If this were not the case, high priority tasks could monopolize the system.
> But, it also creates problems for when a interactive process becomes a > cpu hog. Like this the detection should be faster, but should be slowed > down somewhat.
I agree, although I do think it responds fairly quick. But, regardless, this is why I am interested in Nick's work. The interactivity estimator can never be perfect.
> But, hogs would instead cause a context switch hell and lessen the > throughput on server loads...
Hm, why?
> I don't see how priorities would be questioned... Since, all i say is > that a task that gets preempted should have a guaranteed time on the cpu > so that we don't waste cycles doing context switches all the time.
But latency is important.
Robert Love
- 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/
| |