
Hello, Le 01/03/2017 à 18:51, Antoine Pitrou a écrit :
On Wed, 1 Mar 2017 12:28:24 -0500 Barry Warsaw <barry@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_scmTRDmVauBprKL8ei...
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_pQs9trI... Hope it can help, Kind regards, ...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