Mailman 3 September 2005 - Python-Dev

python optimization
by Neal Becker Sept. 16, 2005

Sept. 16, 2005

I use cpython. I'm accustomed (from c++/gcc) to a style of coding that is highly readable, making the assumption that the compiler will do good things to optimize the code despite the style in which it's written. For example, I assume constants are removed from loops. In general, an entity is defined as close to the point of usage as possible. I don't know to what extent these kind of optimizations are available to cpython. For example, are constant calculations removed from loops? How about functions? Is there a significant cost to putting a function def inside a loop rather than outside?

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IMPORTANT: 2.4.2c1 Wednesday, 21st September - branch will be closed for a week.
by Anthony Baxter Sept. 16, 2005

Sept. 16, 2005

So we'll be cutting the 2.4.2 release candidate on Wednesday the 21st (next week). Can people please make sure they are running the test suite fully for any checkins between now and then? Also, please consider the release24-maint branch closed from 0000 UTC/GMT on the 21st - this will remain closed for all but critical brown-paper-bag bugs for a week, until we (hopefully) cut 2.4.2 final on the 28th. I'll send a reminder email about 12 hours out from the branch close. Anthony

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python-checkins reply-to
by Barry Warsaw Sept. 15, 2005

Sept. 15, 2005

Raymond requested, and Guido concurred, that the python-checkins mailing list Reply-To header munging be turned off. I've now done this. Previously, follow-ups to checkins would be addressed to python-dev. Now, follow-ups will stay on the python-checkins list and will not appear here, unless the poster explicitly redirects it. -Barry

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Re: [Python-Dev] Variant of removing GIL.
by Sokolov Yura Sept. 15, 2005

Sept. 15, 2005

Corrections: Now, every thread keeps one n queue of objects to incref and second queue to decref. Both can be implemented as array, cause they will be freed at once. Initially, every thread acquires GIL for "read". Py_INCREF places a ref into a incref queue of a thread, Py_DECREF places a ref into a decref queue of a thread. When queue has became full or "100" instruction left ( :-) , it usefull), thread releases GIL for "read" and acquires for "write", when first process acquire it he: walk throw all incref queues in all threads, incref all thouse refs, and clear queues. then walk throw all decref queues in all threads, decref all thouse refs, and clear queues After all he acquires GIL for "read". Other processes could stupidly repeat it founding clear queues. Since there only one thread works as a "garbage collector", we will not loose any incref and decref.

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Re: [Python-Dev] python/dist/src/Lib urllib.py, 1.165.2.1, 1.165.2.2
by Reinhold Birkenfeld Sept. 15, 2005

Sept. 15, 2005

rhettinger(a)users.sourceforge.net wrote: > Update of /cvsroot/python/python/dist/src/Lib > In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv31892 > > Modified Files: > Tag: release24-maint > urllib.py > Log Message: > Sync-up with patches to the head. > Includes SF 1016880: urllib.urlretrieve silently truncates downloads > and the performance fix-ups. This last patch includes a new exception, are you sure that this can be safely backported? If so, the documentation changes must be backported, too. Reinhold -- Mail address is perfectly valid!

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Weekly Python Patch/Bug Summary
by Kurt B. Kaiser Sept. 15, 2005

Sept. 15, 2005

Patch / Bug Summary ___________________ Patches : 343 open ( +1) / 2927 closed ( +4) / 3270 total ( +5) Bugs : 908 open ( +0) / 5245 closed (+13) / 6153 total (+13) RFE : 189 open ( +1) / 185 closed ( +0) / 374 total ( +1) New / Reopened Patches ______________________ Allow to restrict ModuleFinder to get "direct" dependencies (2005-09-08) http://python.org/sf/1284670 opened by Scherer Michael pygettext - provide comments to help translators (2005-09-11) http://python.org/sf/1288056 opened by Toby Dickenson FreeBSD 5.3 and upward has thread-safe getaddrinfo(3) (2005-09-12) http://python.org/sf/1288833 opened by Maxim Sobolev Fix reload() error message (2005-09-13) CLOSED http://python.org/sf/1290454 opened by Collin Winter mmap with unsigned int offset and cross build for ppc (2005-09-14) http://python.org/sf/1291169 opened by José Pedro Pereira Valente de M Patches Closed ______________ Fix reload() error message (2005-09-13) http://python.org/sf/1290454 closed by birkenfeld HP-UX ia64 64-bit Python executable (2005-06-21) http://python.org/sf/1225212 closed by gvanrossum AIX port from Elemental Security (2005-09-07) http://python.org/sf/1284289 closed by gvanrossum new patch for fixing skipitem() in getargs.c (2005-06-01) http://python.org/sf/1212928 closed by birkenfeld New / Reopened Bugs ___________________ traceback module can return undecodable byte strings (2005-09-08) http://python.org/sf/1284496 opened by Stuart Bishop logging module's setLoggerClass not really working (2005-09-08) http://python.org/sf/1284928 opened by Rotem Yaari urllib.quote is too slow (2005-09-08) http://python.org/sf/1285086 opened by Tres Seaver Call to cmd.exe fails (2005-09-08) CLOSED http://python.org/sf/1285325 opened by Alex Luso Digest Authentication not working in all cases (2005-09-08) http://python.org/sf/1285440 opened by Jakob Simon-Gaarde re special sequence '\w' (2005-09-09) CLOSED http://python.org/sf/1285809 opened by ChristianJ Python code.interact() and UTF-8 locale (2005-09-12) http://python.org/sf/1288615 opened by STINNER Victor timedelta multiply and divide by floating point (2005-09-12) http://python.org/sf/1289118 opened by Daniel Stutzbach distutils extension library path bug on cygwin (2005-09-12) http://python.org/sf/1289136 opened by John Whitley PyDoc crashes at os.py line 133 (2005-09-12) CLOSED http://python.org/sf/1289210 opened by Colin J. Williams cjkcodec compile error under AIX 5.2 on symbol 100_encode (2005-09-13) http://python.org/sf/1290333 opened by Deron Meranda --no-compile option has no effect (2005-09-13) CLOSED http://python.org/sf/1290382 opened by Tim Peters strptime(): can't switch locales more than once (2005-09-13) CLOSED http://python.org/sf/1290505 opened by Adam Monsen SSLObject breaks read semantics (2005-09-14) http://python.org/sf/1291446 opened by Jonathan Ellis Bugs Closed ___________ Call to cmd.exe fails (2005-09-08) http://python.org/sf/1285325 deleted by delenca exception when unpickling array.array objects (2005-09-04) http://python.org/sf/1281556 closed by rhettinger PyDoc crashes at os.py line 133 (2005-09-12) http://python.org/sf/1289210 closed by rhettinger --no-compile option has no effect (2005-09-13) http://python.org/sf/1290382 closed by tim_one RE parser too loose with {m,n} construct (2005-05-15) http://python.org/sf/1202493 closed by niemeyer document {m} regex matcher wrt empty matches (2005-01-31) http://python.org/sf/1113484 closed by niemeyer r'\10' as replacement pattern loops in compilation (2004-11-02) http://python.org/sf/1058786 closed by niemeyer re nested conditional matching (?()) doesn't work (2005-09-08) http://python.org/sf/1284341 closed by birkenfeld skipitem() in getargs.c missing some types (2004-02-09) http://python.org/sf/893549 closed by birkenfeld re special sequence '\w' (2005-09-09) http://python.org/sf/1285809 closed by birkenfeld suspected cPickle memory leak (2005-05-13) http://python.org/sf/1201461 closed by birkenfeld splitunc not documented (2005-08-27) http://python.org/sf/1274828 closed by birkenfeld os.startfile() doesn't accept Unicode filenames (2004-08-11) http://python.org/sf/1007046 closed by birkenfeld strptime(): can't switch locales more than once (2005-09-13) http://python.org/sf/1290505 closed by bcannon

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Re: [Python-Dev] [Python-checkins] python/dist/src/Lib/test regrtest.py, 1.171, 1.172 test_ioctl.py, 1.2, 1.3
by Neal Norwitz Sept. 14, 2005

Sept. 14, 2005

> Index: test_ioctl.py > =================================================================== > RCS file: /cvsroot/python/python/dist/src/Lib/test/test_ioctl.py,v > retrieving revision 1.2 > retrieving revision 1.3 > diff -u -d -r1.2 -r1.3 > --- test_ioctl.py 20 Mar 2003 04:33:16 -0000 1.2 > +++ test_ioctl.py 14 Sep 2005 18:09:41 -0000 1.3 > @@ -16,19 +16,23 @@ > > class IoctlTests(unittest.TestCase): > def test_ioctl(self): > - pgrp = os.getpgrp() > + # If this process has been put into the background, TIOCGPGRP returns > + # the session ID instead of the process group id. > + ids = (os.getpgrp(), os.getsid(0)) > tty = open("/dev/tty", "r") > r = fcntl.ioctl(tty, termios.TIOCGPGRP, " ") > - self.assertEquals(pgrp, struct.unpack("i", r)[0]) > + rpgrp = struct.unpack("i", r)[0] > + self.assert_(rpgrp in ids, "%s not in %s" % (rpgrp, ids)) With the change to use unsigned ints in pwd and grp modules, should the struct.unpack() use "I" (capital i) instead of "i"? n

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Term unification
by Reinhold Birkenfeld Sept. 14, 2005

Sept. 14, 2005

Hi, looking at bug #1283289, I saw that the term "keyword parameter" is used in Python/getargs.c, mixed with "keyword argument". Grepping through the source, "keyword parameter" had 43 matches, while "keyword argument" had 430. Should the "parameter" form be extinguished? Reinhold (And BTW, should bug #1283289 be fixed as the poster suggests?) -- Mail address is perfectly valid!

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speeding up list append calls
by Neal Norwitz Sept. 14, 2005

Sept. 14, 2005

Tim made me do it! http://groups.google.com/group/comp.lang.python/msg/9075a3bc59c334c9 For whatever reason, I was just curious how his code could be sped up. I kept seeing this append method being called and I thought, "there's an opcode for that." What happens if you replace var.append() with the LIST_APPEND opcode. # standard opcodes $ ./python ./Lib/timeit.py -n 1000 -s 'import foo' 'foo.foo1(10000)' 1000 loops, best of 3: 3.66 msec per loop # hacked version $ ./python ./Lib/timeit.py -n 1000 -s 'import foo' 'foo.foo2(10000)' 1000 loops, best of 3: 1.74 msec per loop The patch and foo.py are attached. This code doesn't really work in general. It assumes that any append function call is a list method, which is obviously invalid. But if a variable is known to be a list (ie, local and assigned as list (BUILD_LIST) or a list comprehension), could we do something like this as a peephole optimization? I'm not familiar enough with some dynamic tricks to know if it there are conditions that could break this. Probably useless, but it was interesting to me at the time. n

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Fwd: [Python-checkins] python/dist/src/Misc NEWS, 1.1193.2.94, 1.1193.2.95
by Guido van Rossum Sept. 14, 2005

Sept. 14, 2005

I have no way to test this code on Windows (or on other UNIX platforms besides Linux and AIX). Hopefully someone can verify whether it breaks anything. ---------- Forwarded message ---------- From: gvanrossum(a)users.sourceforge.net <gvanrossum(a)users.sourceforge.net> Date: Sep 14, 2005 11:15 AM Subject: [Python-checkins] python/dist/src/Misc NEWS, 1.1193.2.94, 1.1193.2.95 To: python-checkins(a)python.org Update of /cvsroot/python/python/dist/src/Misc In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv24791/Misc Modified Files: Tag: release24-maint NEWS Log Message: - Changes donated by Elemental Security to make it work on AIX 5.3 with IBM's 64-bit compiler (SF patch #1284289). This also closes SF bug #105470: test_pwd fails on 64bit system (Opteron). Index: NEWS =================================================================== RCS file: /cvsroot/python/python/dist/src/Misc/NEWS,v retrieving revision 1.1193.2.94 retrieving revision 1.1193.2.95 diff -u -d -r1.1193.2.94 -r1.1193.2.95 --- NEWS 14 Sep 2005 17:54:39 -0000 1.1193.2.94 +++ NEWS 14 Sep 2005 18:15:03 -0000 1.1193.2.95 @@ -12,6 +12,10 @@ Core and builtins ----------------- +- Changes donated by Elemental Security to make it work on AIX 5.3 + with IBM's 64-bit compiler (SF patch #1284289). This also closes SF + bug #105470: test_pwd fails on 64bit system (Opteron). + - Changes donated by Elemental Security to make it work on HP-UX 11 on Itanium2 with HP's 64-bit compiler (SF patch #1225212). _______________________________________________ Python-checkins mailing list Python-checkins(a)python.org http://mail.python.org/mailman/listinfo/python-checkins -- --Guido van Rossum (home page: http://www.python.org/~guido/)

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