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Date:   Mon, 9 Jan 2023 20:51:44 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Willy Tarreau <w@1wt.eu>, Theodore Ts'o <tytso@mit.edu>,
        kernel list <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@osdl.org>
Subject: Re: Dhrystone -- userland version
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Hi!

> >   count=3D1666675 us50=3D20178 us250=3D99913 diff=3D79735 cpu_MHz=3D418=
0.536 tsc50=3D42614718 tsc250=3D211016124 diff=3D101 rdtsc_MHz=3D2112.014
> >
> > 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 :-)).
>=20
> Seeing the rdtsc stuff, I was a bit skeptical, but it seems to work
> fine on arm32 and rv64.
>=20
> Unfortunately you forgot to add a LICENSE file ;-)
>=20
> Alternatively, I can use the C version of BogoMIPS.  Which has its
> own merits and reputation.

I'd expect BogoMIPS to be _much_ worse than Dhrystone. If all the
cores are same, it should be good enough, but...

> The nice thing about Dhrystones is that people still publish numbers
> for comparison, also DMIPS/MHz and DMIPS/mW.

=2E..and there seems to be no replacement for that. Dhrystones seem to
become the standard in RISC-V community at least.

Best regards,
								Pavel
--=20
People of Russia, stop Putin before his war on Ukraine escalates.

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