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

[Louis Bouchard]

Hello,

Le 01/03/2017 à 18:51, Antoine Pitrou a écrit :
> On Wed, 1 Mar 2017 12:28:24 -0500
> Barry Warsaw <barry at python.org> wrote:
>>
>> Louis (Cc'd here) has done a ton of work to measure and analyze the problem,
>> but we've more or less hit a roadblock, so we're taking the issue public to
>> see if anybody on this mailing list has further ideas.  A detailed analysis is
>> available in this Google doc:
>>
>> https://docs.google.com/document/d/1zrV3OIRSo99fd2Ty4YdGk_scmTRDmVauBprKL8eij6w/edit
>>
>> The document should be public for comments and editing.
> 
> I may be misunderstanding the document, but this lacks at least a
> comparison of the *same* interpreter version with different compiler
> versions.
> 
> As for the high level: what if the training set used for PGO in Xenial
> has become skewed or inadequate?  Just a thought, as it would imply
> that PGO+LTO uses wrong information for code placement and other
> optimizations.
> 
> Regards
> 
> Antoine.
> 

Indeed, this is something that is in the history of the LP bug so here is the
URL where those comparison can be found :

https://docs.google.com/spreadsheets/d/1MyNBPVZlBeic1OLqVKe_bcPk2deO_pQs9trIfOFefM0/edit#gid=2034603487

Hope it can help,

Kind regards,

...Louis


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