Re: Dhrystone -- userland version

[Willy Tarreau <w@1wt.eu>]

Hi Geert,

On Mon, Jan 09, 2023 at 10:28:09AM +0100, Geert Uytterhoeven wrote:
> Hi Ted,
> 
> On Mon, Jan 9, 2023 at 1:45 AM Theodore Ts'o <tytso@mit.edu> wrote:
> > On Sun, Jan 08, 2023 at 07:47:07PM +0100, Pavel Machek wrote:
> > > > However, as this is not Linux-specific, how hard can it be to convince
> > > > your distro to include https://github.com/qris/dhrystone-deb.git?
> > > > Usually, when I have a full userspace available, I just clone the above,
> > > > and debuild it myself.
> > >
> > > Dunno. I'd not solve it if package was in Debian, but it is not.
> >
> > I would suspect the better long-term solution would be to get the
> > package into Debian, since that will be easier for people to use.  I
> > suspect the reason why most distros don't include it is because it
> > really is a **terrible** benchmark for most use cases.
> 
> My use case is verifying the CPU core clock rate when working on
> the clock driver and/or cpufreq.  I can easily measure e.g. SPI or
> UART clock rates
> externally, but not CPU core clock rates.

Then maybe you'd rather use this:

   https://github.com/wtarreau/mhz

E.g.:

  $ ./mhz 10
  count=1666675 us50=20089 us250=100748 diff=80659 cpu_MHz=4132.645 tsc50=42427696 tsc250=212780620 diff=102 rdtsc_MHz=2112.014
  count=1666675 us50=20271 us250=101282 diff=81011 cpu_MHz=4114.688 tsc50=42813060 tsc250=213905908 diff=102 rdtsc_MHz=2111.970
  count=1666675 us50=20405 us250=100344 diff=79939 cpu_MHz=4169.867 tsc50=43094116 tsc250=211927426 diff=101 rdtsc_MHz=2112.027
  count=1666675 us50=20239 us250=100249 diff=80010 cpu_MHz=4166.167 tsc50=42744302 tsc250=211727114 diff=101 rdtsc_MHz=2112.021
  count=1666675 us50=20182 us250=100482 diff=80300 cpu_MHz=4151.121 tsc50=42624768 tsc250=212217884 diff=101 rdtsc_MHz=2111.994
  count=1666675 us50=20153 us250=100151 diff=79998 cpu_MHz=4166.792 tsc50=42562818 tsc250=211519326 diff=101 rdtsc_MHz=2112.009
  count=1666675 us50=20281 us250=99803 diff=79522 cpu_MHz=4191.733 tsc50=42832298 tsc250=210784252 diff=100 rdtsc_MHz=2112.019
  count=1666675 us50=20104 us250=99841 diff=79737 cpu_MHz=4180.431 tsc50=42461284 tsc250=210862414 diff=101 rdtsc_MHz=2111.957
  count=1666675 us50=20088 us250=100287 diff=80199 cpu_MHz=4156.349 tsc50=42423974 tsc250=211807066 diff=101 rdtsc_MHz=2112.035
  count=1666675 us50=20178 us250=99913 diff=79735 cpu_MHz=4180.536 tsc50=42614718 tsc250=211016124 diff=101 rdtsc_MHz=2112.014

It's also what's used by sbc-bench to verify that CPU vendors are not
cheating in the embedded world. It's very simple, and not arch-dependent
nor compiler-dependent (at least as long as you don't build at -O0 :-)).

Just my two cents,
Willy