Issue 11089: ConfigParser 50x slower in 2.7 (original) (raw)

Created on 2011-02-01 14:04 by vlachoudis, last changed 2022-04-11 14:57 by admin. This issue is now closed.

Files
File name Uploaded Description Edit
ConfigParserTest.py vlachoudis,2011-02-01 14:04
configparser.patch rhettinger,2011-02-02 02:43 Py2.7 patch for ConfigParser.py
configparser.patch rhettinger,2011-02-02 21:19 configparser.patch
Messages (9)
msg127699 - (view) Author: Vasilis (vlachoudis) Date: 2011-02-01 14:04
The ConfigParser class in 2.7 is almost >50 times slower than in the 2.6 which for large files it renders it almost unusable. Actually the speed decrease depends on the amount of the stored data Results from test program: Python 2.7 (r27:82500, Sep 16 2010, 18:02:00) on 3.5GHz Fedora14 64bit machine ConfigParser 166.307140827 RawConfigParser 0.1887819767 Python 2.6.4 (r264:75706, Jun 4 2010, 18:20:31) on 3.0GHz Fedora13 64bit machine ConfigParser 4.24494099617 RawConfigParser 0.172905921936
msg127710 - (view) Author: Stefan Krah (skrah) * (Python committer) Date: 2011-02-01 22:06
If OrderedDict is used, the test case quickly uses 8GB of memory. With this change (I'm not suggesting this as a fix!), the timings are normal: Index: Lib/ConfigParser.py =================================================================== --- Lib/ConfigParser.py (revision 88298) +++ Lib/ConfigParser.py (working copy) @@ -92,6 +92,7 @@ except ImportError: # fallback for setup.py which hasn't yet built _collections _default_dict = dict +_default_dict = dict import re
msg127713 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-02 01:46
Commenting-out the ``c.set(section,"item#%d"%(i),str(i))`` calls shows that that is not where the problem lies for the ConfigParser() class. The issue seems confined to ConfigParser.get(). The RawConfigParser() class doesn't seem to have the same issue. Looking at the 2.7 code for ConfigParser.get() shows that it is doing a lot more than just getting. For example, it does a full copy of defaults dictionary on every call !? I'll look at it more shortly.
msg127715 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-02 02:43
Attaching a patch that fixes the algorithmic atrocities by using the Chainmap recipe: http://code.activestate.com/recipes/305268-chained-map-lookups
msg127726 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-02 08:39
Fixed for 2.7 in r88318. Will make a similar fix for 3.1.4 and for 3.2.1.
msg127761 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-02 21:19
Attaching patch for Python 3.2. Georg, I was think of waiting for 3.2.1 for this one, but it can go into 3.2.0 RC2 if you prefer.
msg127764 - (view) Author: Georg Brandl (georg.brandl) * (Python committer) Date: 2011-02-02 21:29
3.2.1 should be fine.
msg127766 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-02 21:37
Fixed 3.1 in r88323.
msg128986 - (view) Author: Raymond Hettinger (rhettinger) * (Python committer) Date: 2011-02-21 19:43
See r88469 and r88470.
History
Date User Action Args
2022-04-11 14:57:12 admin set github: 55298
2011-02-21 19:43:02 rhettinger set status: open -> closedmessages: + resolution: later -> fixednosy:skip.montanaro, georg.brandl, rhettinger, skrah, lukasz.langa, vlachoudis
2011-02-02 21:37:48 rhettinger set versions: - Python 3.1nosy:skip.montanaro, georg.brandl, rhettinger, skrah, lukasz.langa, vlachoudismessages: + assignee: georg.brandl -> rhettingerresolution: later
2011-02-02 21:29:21 georg.brandl set nosy:skip.montanaro, georg.brandl, rhettinger, skrah, lukasz.langa, vlachoudismessages: +
2011-02-02 21:19:06 rhettinger set files: + configparser.patchnosy: + georg.brandlmessages: + assignee: rhettinger -> georg.brandl
2011-02-02 08:39:47 rhettinger set assignee: lukasz.langa -> rhettingerversions: - Python 2.7messages: + nosy:skip.montanaro, rhettinger, skrah, lukasz.langa, vlachoudis
2011-02-02 02:43:22 rhettinger set files: + configparser.patchmessages: + keywords: + patchnosy:skip.montanaro, rhettinger, skrah, lukasz.langa, vlachoudis
2011-02-02 01:46:44 rhettinger set nosy: + rhettingermessages: +
2011-02-01 22:33:25 pitrou set nosy:skip.montanaro, skrah, lukasz.langa, vlachoudisversions: + Python 3.1, Python 3.2
2011-02-01 22:07:00 skrah set nosy: + skrahmessages: +
2011-02-01 14:30:27 skip.montanaro set nosy: + skip.montanaro
2011-02-01 14:23:35 pitrou set assignee: lukasz.langanosy: + lukasz.langa
2011-02-01 14:04:42 vlachoudis create