Re: [PATCH 1/2] benchtests: Memory walking benchmark for memcpy

[Carlos O'Donell <carlos at redhat dot com>]

On 09/18/2017 11:40 AM, Siddhesh Poyarekar wrote:
> This benchmark is an attempt to eliminate cache effects from string
> benchmarks.  The benchmark walks both ways through a large memory area
> and copies different sizes of memory and alignments one at a time
> instead of looping around in the same memory area.  This is a good
> metric to have alongside the other memcpy benchmarks, especially for
> larger sizes where the likelihood of the call being done only once is
> pretty high.
> 
> The benchmark is unlike other string benchmarks in that it prints the
> total data rate achieved during a walk across the memory and not the
> time taken per execution.
> 
> 	* benchtests/bench-memcpy-walk.c: New file.
> 	* benchtests/Makefile (string-benchset): Add it.
I like the idea, and the point that the other benchmark eventually degrades
into measuring L1 performance an interesting insight.

I do not like that it produces total data rate not time taken per execution.
Why the change? If time taken per execution was OK before, why not here?

-- 
Cheers,
Carlos.