[Python-Dev] Help requested with Python 2.7 performance regression

[Louis Bouchard]

Hello,

Le 03/03/2017 à 08:27, Nick Coghlan a écrit :
> On 2 March 2017 at 07:00, Victor Stinner <victor.stinner at gmail.com
> <mailto:victor.stinner at gmail.com>> wrote:
> 
>     Hi,
> 
>     Your document doesn't explain how you configured the host to run
>     benchmarks. Maybe you didn't tune Linux or anything else? Be careful
>     with modern hardware which can make funny (or not) surprises.
> 
> 

This was 'almost' intentional, as no specific O/S tuning was done. The intent is
to compare performance between two specific versions of the interperter, not to
target any gain in performance. Such tuning would suposedly have a linear impact
on both version. If not, then the compiler definitively does some funky things
that I want to be aware of.

> Victor, do you know if you or anyone else has compared the RHEL/CentOS 7.x
> binaries (Python 2.7.5 + patches, built with GCC 4.8.x) with the Fedora 25
> binaries (Python 2.7.13 + patches, built with GCC 6.3.x)?
> 
> I know you've been using perf to look for differences between *Python* major
> versions, but this would be more about using Python's benchmark suite to
> investigate the performance of *gcc*, since it appears that may be the culprit here.
> 

Now this is an interesting test that I can probably do myself to a certain
extent using containers and/or VM on the same hardware. While it will be no mean
a strong validation of the performances, I may be able to confirm a similar
trend in the results before going forward with tests on baremetal.


> Cheers,
> Nick.
> 

Thanks,

...Louis


-- 
Louis Bouchard
Software engineer, Cloud & Sustaining eng.
Canonical Ltd
Ubuntu developer                       Debian Maintainer
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