lkml.org 
[lkml]   [2006]   [Nov]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: + sched-use-tasklet-to-call-balancing.patch added to -mm tree
Date
Christoph Lameter wrote on Tuesday, November 07, 2006 1:50 PM
> On Tue, 7 Nov 2006, Chen, Kenneth W wrote:
> > > What broke the system was the disabling of interrupts over long time
> > > periods during load balancing.
> > The previous global load balancing tasket could be an interesting data point.
>
> Yup seems also very interesting to me. We could drop the staggering code
> f.e. if we would leave the patch as is. Maybe there are other ways to
> optimize the code because we know that there are no concurrent
> balance_tick() functions running.
>
> > Do you see a lot of imbalance in the system with the global tasket? Does it
> > take prolonged interval to reach balanced system from imbalance?
>
> I am rather surprised that I did not see any problems but I think we would
> need some more testing. It seems that having only one load balance
> running at one time speeds up load balacing in general since there is
> less lock contention.


I ran majority of micro-benchmarks from LKP project with global load
balance tasklet. (http://kernel-perf.sourceforge.net)

Result is here:
http://kernel-perf.sourceforge.net/sched/global-load-bal.txt

All results are within noise range. The global tasklet does a fairly good job especially on context switch intensive workload like
aim7, volanomark, tbench
etc. Note all machines are non-numa platform.

Base on the data, I think we should make the load balance tasklet one per numa
node instead of one per CPU.

- Ken
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-11-10 07:21    [W:0.112 / U:0.316 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site