On Mon, Jan 28, 2008 at 01:32:53PM +0100, Ingo Molnar wrote:

* Peter Zijlstra [off-list ref] wrote:

quoted

quoted

      * With CONFIG_FAIR_USER_SCHED disabled, there are severe
        interactivity hickups with a niced CPU hog and top running. This
        started with commit 810e95ccd58d91369191aa4ecc9e6d4a10d8d0c8. 

The revert at the bottom causes the wakeup granularity to shrink for + 
nice and to grow for - nice. That is, it becomes easier to preempt a + 
nice task, and harder to preempt a - nice task.

i think it would be OK to do half of this: make it easier to preempt a 
+nice task.

Hmm .. I doubt whether that would help Michel's case, as he seems to be running
+niced tasks and having problems getting control over his desktop.

Something is basically wrong here ..

Michel, do you really need the -nice portion as well? It's 
not a problem to super-preempt positively reniced tasks, but it can be 
quite annoying if negatively reniced tasks have super-slices.

-- 
Regards,
vatsa