Re: collecting simple benchmark scripts?

[Laura Abbott <labbott@redhat.com>]

On 02/14/2018 02:50 PM, Kees Cook wrote:
> Hi,
> 
> In a separate thread, some folks were looking for some simple
> benchmarks for evaluating various changes to kernel internals (as
> opposed to the much more focused things like xfstests). For me, this
> has been an area of lore and passed-around scripts, and it seems like
> maybe we should have a subdirectory of tools/testing/benchmarks/ or
> something to collect these?
> 
> (Or maybe this already exists and I've totally missed it?)
> 
> I've got at least one micro-benchmark in
> tools/testing/selftests/seccomp/seccomp_benchmark.c, and searches show
> tools/testing/selftests/vm/gup_benchmark.c too, but I was thinking of
> either more generali things more like the famous "kernel build
> benchmark" or a wrapper for running hackbench to get some statistics
> out of it, etc.
> 
> Or, I guess, at least collecting all the micro-benchmarks in some
> single place, as they're a bit scattered.
> 
> I'm sure I'm not remotely the first person to bring this up, but my
> attempts at searches for this have failed.
> 
> Thoughts?
> 
> -Kees
> 

This is the script I've been using for hackbench since it can
be noisy. I expect someone to tell me the math is wrong but
I'd be happy to throw this in a repo if others are interested

#!/bin/sh

CNT=100
mean=0.0
M2=0.0
for i in $(seq 1 $CNT); do
	echo $i
	r=`hackbench -g 20 -l 1000 | grep Time | cut -d ' ' -f 2`
	d_calc="$r-$mean"
         d=`echo $d_calc | bc -l`
	mean_calc="$mean+($d/$i)"
	mean=`echo $mean_calc | bc -l`
	M2_calc="$M2+($d*($r-$mean))"
	M2=`echo  $M2_calc| bc -l`
done

echo "mean $mean"
V_calc="$M2/$(($CNT-1))"
V=`echo $V_calc | bc -l`
DEV_calc="sqrt($V)"
DEV=`echo $DEV_calc | bc -l`
echo "variance $V"
echo "stdev $DEV"