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Author pablogsal
Recipients Mark.Shannon, jdemeyer, pablogsal, petr.viktorin, rhettinger
Date 2019-07-11.11:26:56
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1562844416.61.0.409622240812.issue37562@roundup.psfhosted.org>
In-reply-to
Content
Many functions are significantly slower after commit aacc77fbd77640a8f03638216fa09372cc21673d was applied:

aacc77fbd77640a8f03638216fa09372cc21673d is the first bad commit
commit aacc77fbd77640a8f03638216fa09372cc21673d
Author: Jeroen Demeyer <J.Demeyer@UGent.be>
Date:   Wed May 29 20:31:52 2019 +0200

    bpo-36974: implement PEP 590 (GH-13185)


    Co-authored-by: Jeroen Demeyer <J.Demeyer@UGent.be>
    Co-authored-by: Mark Shannon <mark@hotpy.org>


Experiment in 3.8 
-----------------

./python -m perf timeit -s '_len=len' '_len("hello")'
.....................
Mean +- std dev: 157 ns +- 3 ns


Experiment in parent of aacc77fbd77640a8f03638216fa09372cc21673d
----------------------------------------------------------------

python -m perf timeit -s '_len=len' '_len("hello")'
.....................
Mean +- std dev: 133 ns +- 3 ns


The same regression happens consistently in many other functions (hex, len, deque methods....)
History
Date User Action Args
2019-07-11 11:26:56pablogsalsetrecipients: + pablogsal, rhettinger, petr.viktorin, Mark.Shannon, jdemeyer
2019-07-11 11:26:56pablogsalsetmessageid: <1562844416.61.0.409622240812.issue37562@roundup.psfhosted.org>
2019-07-11 11:26:56pablogsallinkissue37562 messages
2019-07-11 11:26:56pablogsalcreate