[Speed] intel_pstate C0 bug on isolated CPUs with the performance governor

[Antoine Pitrou]

On Fri, 23 Sep 2016 01:19:54 +0200
Victor Stinner <victor.stinner at gmail.com>
wrote:
> 
> While analyzing a performance regression (
> http://bugs.python.org/issue28243 ) , I had a major issue with my
> benchmark. Suddenly, for no reason, after 30 minutes of benchmarking,
> the benchmark became 2x FASTER...

Did the benchmark really become 2x faster, or did the clock become 2x
slower?

If you found a magic knob in your CPU that suddently makes it 2x
faster, many people would probably like to hear about it ;-)

> If you have an Intel CPU, use Linux, have a CPU with multiple physical
> cores and have 15 minutes to run a test, I would appreciate if you can
> try to reproduce the bug!

Can you tell us how to "reproduce"?

Regards

Antoine.