On Sunday 22 April 2007 19:14, Willy Tarreau wrote: > On Sun, Apr 22, 2007 at 06:53:58PM +1000, Con Kolivas wrote: > > On Sunday 22 April 2007 18:06, Willy Tarreau wrote: > > > On Sun, Apr 22, 2007 at 05:31:58PM +1000, Con Kolivas wrote: > > > > On Sunday 22 April 2007 17:27, Con Kolivas wrote: > > > > > On Sunday 22 April 2007 17:00, Willy Tarreau wrote: > > > > > > On Sun, Apr 22, 2007 at 02:41:48PM +1000, Con Kolivas wrote: > > > > > > > A significant bugfix for SMP balancing was just posted for the > > > > > > > staircase deadline cpu scheduler which improves behaviour > > > > > > > dramatically on any SMP machine. > > > > > > > > > > > > > > Thanks to Willy Tarreau for noticing likely fault point. > > > > > > > > > > > > > > Also requested was a version in the Makefile so this version of > > > > > > > the patch adds -sd045 to the kernel version. > > > > > > > > > > > > Con, I'm sorry, but it is worse with this one :-( > > > > > > > > > > Well that was quick testing, thanks. > > > > > > > > > > > The lag when typing in xterms is even more noticeable and vmstat > > > > > > output oscillates between 8 and 65, with idle rates around 50%, > > > > > > as you can see below : > > > > > > > > > > > > Renicing X or not does not change anything here. > > > > > > > > > > > > I suspect that the bug you fixed was hiding another one :-/ > > > > > > If you want me to test another patch, feel free to ask. > > > > > > > > Just as a debug point could you please try this patch? Thanks. > > > > > > OK, this time, the ocbench took ages to start. They appeared > > > immediately but very few of them (less than 8 out of 64) really started > > > to work. The system remained very responsive and smooth during the > > > test. But I guess I know why : all the load was sent to CPU 0 : > > > > Shouldn't have affected smp balancing at all, but try this on top of the > > ontop please? Thanks > > Does not change anything. There clearly is a huge regression somewhere :-/ > The second CPU is not used by ocbench, and again, out of 64 tasks, only > a small bunch (between 4 and 8) do something. > > Con, you should review the changes between 0.44 and 0.45, I think you > introduced a bug which broke fairness while fixing another one.
Ok I was able to find time on dual core and could reproduce your problem. Testing something now that I think might be responsible. -- -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/
