original ) (raw )Created on 2011-09-23 04:48 by jpeel , last changed 2022-04-11 14:57 by admin . This issue is now closed .
Messages (6)
msg144436 - (view) Author: Justin Peel (jpeel)
Date: 2011-09-23 04:48
Attached small diff speeds up extracting a gzipped tarball on my machine using python 3.2 by 3-5%. It will probably be a larger percentage on machines that have faster hard drives (mine is 5400rpm). Basically, the changes speed up calculating the checksums by only doing one slice rather than four and call struct.unpack twice rather than four times. We are able to use less unpack calls because 'x' means to skip a byte.
msg144442 - (view) Author: (poq)
Date: 2011-09-23 13:04
I don't think you even need the slice, if you use unpack_from.
msg144466 - (view) Author: Justin Peel (jpeel)
Date: 2011-09-23 18:32
poq, You're quite right. I've added that change too. By the way, four unnecessary extra tuples are no longer being created for each call to this function too because of these changes.
msg160931 - (view) Author: Serhiy Storchaka (serhiy.storchaka) *
Date: 2012-05-16 21:01
Justin, perhaps of interest to the patch would be better if you provide any microbenchmark.
msg160992 - (view) Author: Roundup Robot (python-dev)
Date: 2012-05-17 17:53
New changeset c62fa6892424 by Ross Lagerwall in branch 'default': Issue #13031 : Small speed-up for tarfile when unzipping tarfiles. http://hg.python.org/cpython/rev/c62fa6892424
msg160994 - (view) Author: Ross Lagerwall (rosslagerwall)
Date: 2012-05-17 18:24
Nice work, thanks!
History
Date
User
Action
Args
2022-04-11 14:57:21
admin
set
github: 57240
2012-05-17 18:24:11
rosslagerwall
set
status: open -> closedmessages: + assignee: lars.gustaebel -> rosslagerwall resolution: fixedstage: resolved
2012-05-17 17:53:35
python-dev
set
nosy: + python-dev messages: +
2012-05-16 21:01:27
serhiy.storchaka
set
messages: +
2012-05-16 20:33:48
rosslagerwall
set
nosy: + rosslagerwall
2012-04-07 16:11:56
serhiy.storchaka
set
nosy: + serhiy.storchaka
2011-09-23 18:32:41
jpeel
set
files: + cpython_tarfile2.diff messages: +
2011-09-23 16:33:35
eric.araujo
set
title: [PATCH] small speed-up for tarfile.py when unzipping tarballs -> small speed-up for tarfile.py when unzipping tarballs
2011-09-23 13:04:54
poq
set
nosy: + poq messages: +
2011-09-23 06:46:23
lars.gustaebel
set
priority: normal -> lowassignee: lars.gustaebel nosy: + lars.gustaebel versions: + Python 3.3, - Python 2.7, Python 3.2
2011-09-23 04:50:04
jpeel
set
type: performance
2011-09-23 04:48:55
jpeel
create
