On Monday 12 March 2007 18:48, Con Kolivas wrote: > On Monday 12 March 2007 18:22, Mike Galbraith wrote: > > On Sun, 2007-03-11 at 13:10 +0100, Ingo Molnar wrote: > > > * Mike Galbraith <[EMAIL PROTECTED]> wrote: > > > > > Full patch for 2.6.21-rc3-mm2: > > > > > http://ck.kolivas.org/patches/staircase-deadline/2.6.21-rc3-mm2-rsd > > > > >l- 0.29.patch > > > > > > > > I'm seeing a cpu distribution problem running this on my P4 box. > > > > > > > > With 2.6.21-rc3, X/Gforce maintain their ~50% cpu (remain smooth), > > > > and the encoders (100%cpu bound) get whats left when Amarok isn't > > > > eating it. > > > > > > > > I plunked the above patch into plain 2.6.21-rc3 and retested to > > > > eliminate other mm tree differences, and it's repeatable. The nice 5 > > > > cpu hogs always receive considerably more that the nice 0 sleepers. > > > > > > hm. Do you get the same same problem on UP too? (i.e. lets eliminate > > > any SMP/HT artifacts) > > > > Behavior is slightly different with a UP kernel. Neither encoder > > receives more cpu than X, but they each still receive more than gforce. > > The distribution of X/Gforce vs lame/lame averages per eyeball to > > roughly ~50:50. > > > > I noticed Con posted an accounting fix, and applied it. No change. > > So the lames are nice 5 which means they should receive 75% of the cpu that > nice 0 tasks receive so they should get 43% of the cpu... > > Just a couple of questions; > > The X/Gforce case; do they alternate cpu between them? By that I mean when > they're the only thing running does the cpu load summate to 1 or does it > summate to 2?
I'll save you the trouble. I just checked myself and indeed the load is only 1. What this means is that although there are 2 tasks running, only one is running at any time making a total load of 1. So, if we add two other tasks that add 2 more to the load the total load is 3. However if we weight the other two tasks at nice 5, they only add .75 each to the load making a weighted total of 2.5. This means that X+Gforce together should get a total of 1/2.5 or 40% of the overall cpu. That sounds like exactly what you're describing is happening. -- -ck - 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/
