Op Monday 05 March 2007, schreef Willy Tarreau: > On Mon, Mar 05, 2007 at 08:49:29AM +1100, Con Kolivas wrote: > (...) > > > > That's just what it did, but when you "nice make -j4", things (gears) > > > start to stutter. Is that due to the staircase? > > > > gears isn't an interactive task. Apart from using it as a background load > > to check for starvation because it loads up the cpu fully (which a gpu > > intensive but otherwise simple app like this should _not_ do) graphics > > card drivers and interrupts and so on, I wouldn't put much credence on > > gears as anything else. However I suspect that gears will still get a > > fair share of the cpu on RSDL which almost never happens on any other > > scheduler. > > Con, > > I've now given it a try with HZ=250 on my dual-athlon. It works > beautifully. I also quickly checked that playing mp3 doesn't skip during > make -j4, and that gears runs fairly smoothly, since those are the > references people often use. > > But with real work, it's excellent too. When I saturate my CPUs by > injecting HTTP traffic on haproxy, the load is stable and the command line > perfectly responsive, while in the past the load would oscillate and the > command line sometimes stopped to respond for a few seconds. > > I've also launched my scheddos program (you may remember, the one we did a > few experiments with). I could not cause any freeze at all. Plain 2.6.20 > had already improved a lot in this area, but above 4 processes/CPU, > occasional short freezes did still occur. This time, even at 100 processes, > the system was rather slow (of course!) but just as expected, and nothing > more. > > I also tried the good old "dd if=/dev/zero bs=1|...|dd bs=1 of=/dev/null" > and it did not cause any trouble. > > I will boot 2.6 slightly more often to test the code under various > conditions, and I will recommend it to a few people I know who tend to > switch back to 2.4 after one day full of 2.6 jerkiness. > > Overall, you have done a great job ! > > I hope that more people will give it a try, first to help find possible > remaining bugs, and to pronounce in favour of its inclusion in mainline. > > Cheers, > Willy Sounds nice... you might want to put this in the -ck wiki: ck.wikia.com/