Re: [PATCH v2 2/4] sched:Consider imbalance_pct when comparing loads in numa_has_capacity

[Ingo Molnar <mingo@kernel.org>]

* Srikar Dronamraju <srikar@linux.vnet.ibm.com> wrote:

> * Ingo Molnar <mingo@kernel.org> [2015-06-23 10:10:39]:
> > > Please let me know if there are any better ways to observe the
> > > spread. [...]
> > 
> > There are. I see you are using prehistoric tooling, but see the various NUMA 
> > convergence latency measurement utilities in 'perf bench numa':
> > 
> >   vega:~> cat numa01-THREAD_ALLOC
> > 
> >   perf bench numa mem --no-data_rand_walk -p 2 -t 16 -G 0 -P 0 -T 192 -l 1000 -zZ0c $@
> > 
> > You can generate very flexible setups of NUMA access patterns, and measure their 
> > behavior accurately.
> > 
> > It's all so much more capable and more flexible than autonumabench ...
> 
> Okay, thanks for the hint, I will try this out in future.
> 
> > 
> > Also, when you are trying to report numbers for multiple runs, please use 
> > something like:
> > 
> >    perf stat --null --repeat 3 ...
> > 
> > This will run the workload 3 times (doing only time measurement) and report the 
> > stddev in a human readable form.
> > 
> 
> Thanks again for this hint. Wouldnt system time/ user time also matter?

Yeah, would be nice to add stime/utime output to 'perf stat', so that it's an easy 
replacement for /usr/bin/time.

I've Cc:-ed perf folks who might be able to help out.

Thanks,

	Ingo