Re: [PATCH] perf bench sched cpu-matrix benchmark

[Ingo Molnar <mingo@elte.hu>]

* Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> wrote:

> Hi,
> 
> During the discussion of the nohz load balancer fix 
> (https://lkml.org/lkml/2011/9/27/197), Ingo Molnar suggested
> to replace the simple while1 loop, used for publishing the 
> test results with cpu-matrix test. This patch adds cpu-matrix 
> benchmark under perf bench.
> 
> TODO:
> 	- Provide option to run main thread at real-time priority.
> 	- Provide option for changing scheduling priority/policy
> 	  of worker threads.
> 
> 
> perf bench: Add sched cpu-matrix benchmark
> 
> perf bench sched cpu-matrix benchmark is a matrix multiplication
> workload, which can be replaced with the traditional while1 
> cpu hog.
> 
> Example of usage:
> 
> % perf bench sched cpu-matrix 
> # Running sched/cpu-matrix benchmark...
> 
> Multiplication of [20] x [20] matrix, using [1] threads
>  Total time: 0.000170 [sec]
> 
> % perf bench sched cpu-matrix -s1k -t3 
> # Running sched/cpu-matrix benchmark...
> elapsed time = 0.100066 sec, progress = 27270868
> elapsed time = 0.100079 sec, progress = 27299841
> elapsed time = 0.100071 sec, progress = 27253513
> elapsed time = 0.100073 sec, progress = 27272693
> elapsed time = 0.100090 sec, progress = 10208415
> 
> Multiplication of [1024] x [1024] matrix, using [3] threads
>  Total time: 0.500495 [sec]

It would be nice to also print the *size* of the matrix, in MBs or 
so. 1024x1024 of int, long, float ... or double?

Looks pretty useful otherwise. Arnaldo, any objections?

Thanks,

	Ingo