Hello, Le 03/03/2017 à 08:27, Nick Coghlan a écrit :
On 2 March 2017 at 07:00, Victor Stinner <victor.stinner@gmail.com <mailto:victor.stinner@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 GPG : 429D 7A3B DD05 B6F8 AF63 B9C4 8B3D 867C 823E 7A61