On Saturday 10 March 2007 09:29, Matt Mackall wrote: > On Sat, Mar 10, 2007 at 09:18:05AM +1100, Con Kolivas wrote: > > On Saturday 10 March 2007 08:57, Con Kolivas wrote: > > > On Saturday 10 March 2007 08:39, Matt Mackall wrote: > > > > On Sat, Mar 10, 2007 at 08:19:18AM +1100, Con Kolivas wrote: > > > > > On Saturday 10 March 2007 08:07, Con Kolivas wrote: > > > > > > On Saturday 10 March 2007 07:46, Matt Mackall wrote: > > > > > > > My suspicion is the problem lies in giving too much quanta to > > > > > > > newly-started processes. > > > > > > > > > > > > Ah that's some nice detective work there. Mainline does some > > > > > > rather complex accounting on sched_fork including (possibly) a > > > > > > whole timer tick which rsdl does not do. make forks off > > > > > > continuously so what you say may well be correct. I'll see if I > > > > > > can try to revert to the mainline behaviour in sched_fork (which > > > > > > was obviously there for a reason). > > > > > > > > > > Wow! Thanks Matt. You've found a real bug too. This seems to fix > > > > > the qemu misbehaviour and bitmap errors so far too! Now can you > > > > > please try this to see if it fixes your problem? > > > > > > > > Sorry, it's about the same. I now suspect an accounting glitch > > > > involving pipe wake-ups. > > > > > > > > 5x memload: good > > > > 5x execload: good > > > > 5x forkload: good > > > > 5 parallel makes: mostly good > > > > make -j 5: bad > > > > > > > > So what's different between makes in parallel and make -j 5? Make's > > > > job server uses pipe I/O to control how many jobs are running. > > > > > > Hmm it must be those deep pipes again then. I removed any quirks > > > testing for those from mainline as I suspected it would be ok. Guess > > > I"m wrong. > > > > I shouldn't blame this straight up though if NO_HZ makes it better. > > Something else is going wrong... wtf though? > > Just so we're clear, dynticks has only 'fixed' the single non-parallel > make load so far.
Ok, so some of the basics then. Can you please give me the output of 'top -b' running for a few seconds during the whole affair? Thanks very much for your testing so far! -- -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/
