Commit Graph

35 Commits

Author SHA1 Message Date
Jeremy Hylton 37b1a26c89 add list_contains and tuplecontains: efficient implementations of tp_contains 2000-04-27 21:41:03 +00:00
Guido van Rossum 5ce78f8e4e Patch by Charles G Waldman to avoid a sneaky memory leak in
_PyTuple_Resize().  In addition, a change suggested by Jeremy Hylton
to limit the size of the free lists is also merged into this patch.

Charles wrote initially:

"""
Test Case:  run the following code:

class Nothing:
    def __len__(self):
        return 5
    def __getitem__(self, i):
        if i < 3:
            return i
        else:
            raise IndexError, i

def g(a,*b,**c):
    return

for x in xrange(1000000):
    g(*Nothing())


and watch Python's memory use go up and up.


Diagnosis:

The analysis begins with the call to PySequence_Tuple at line 1641 in
ceval.c - the argument to g is seen to be a sequence but not a tuple,
so it needs to be converted from an abstract sequence to a concrete
tuple.  PySequence_Tuple starts off by creating a new tuple of length
5 (line 1122 in abstract.c).  Then at line 1149, since only 3 elements
were assigned, _PyTuple_Resize is called to make the 5-tuple into a
3-tuple.  When we're all done the 3-tuple is decrefed, but rather than
being freed it is placed on the free_tuples cache.

The basic problem is that the 3-tuples are being added to the cache
but never picked up again, since _PyTuple_Resize doesn't make use of
the free_tuples cache.  If you are resizing a 5-tuple to a 3-tuple and
there is already a 3-tuple in free_tuples[3], instead of using this
tuple, _PyTuple_Resize will realloc the 5-tuple to a 3-tuple.  It
would more efficient to use the existing 3-tuple and cache the
5-tuple.

By making _PyTuple_Resize aware of the free_tuples (just as
PyTuple_New), we not only save a few calls to realloc, but also
prevent this misbehavior whereby tuples are being added to the
free_tuples list but never properly "recycled".
"""

And later:

"""
This patch replaces my submission of Sun, 16 Apr and addresses Jeremy
Hylton's suggestions that we also limit the size of the free tuple
list.  I chose 2000 as the maximum number of tuples of any particular
size to save.

There was also a problem with the previous version of this patch
causing a core dump if Python was built with Py_TRACE_REFS.  This is
fixed in the below version of the patch, which uses tupledealloc
instead of _Py_Dealloc.
"""
2000-04-21 21:15:05 +00:00
Guido van Rossum d724b23420 Christian Tismer's "trashcan" patch:
Added wrapping macros to dictobject.c, listobject.c, tupleobject.c,
frameobject.c, traceback.c that safely prevends core dumps
on stack overflow. Macros and functions in object.c, object.h.
The method is an "elevator destructor" that turns cascading
deletes into tail recursive behavior when some limit is hit.
2000-03-13 16:01:29 +00:00
Guido van Rossum bffd683f73 The rest of the changes by Trent Mick and Dale Nagata for warning-free
compilation on NT Alpha.  Mostly added casts etc.
2000-01-20 22:32:56 +00:00
Guido van Rossum 0eb55ac912 Mark Favas was quick to note that the last checkin divides by zero
when n == 0...  So divide by a->ob_size instead which was already
tested for 0.
1999-07-13 05:41:12 +00:00
Guido van Rossum 5bc51f2f27 Appropriate overflow checks so that things like sys.maxint*(1,) can't
dump core.
1999-07-12 23:06:58 +00:00
Guido van Rossum 68055ce6fe When tracing references, reset the type and size of tuples allocated
from the fast free list -- the type (at least) is reset by
_Py_Dealloc().
1998-12-11 14:56:38 +00:00
Guido van Rossum 017f7780a8 Make tuples less hungry -- an extra item was allocated but never used.
Tip by Vladimir Marangozov.
1998-11-16 18:56:03 +00:00
Guido van Rossum 1bb26872f5 Slight rearrangement of some code to make it faster, by Vladimir
Marangozov.
1998-06-26 15:53:50 +00:00
Guido van Rossum 787bdd37a0 PyTuple_SetItem should require that the tuple's refcnt is one! 1997-08-17 16:25:45 +00:00
Guido van Rossum fbbd57e4ca Added _Fini() routines to free up some memory 1997-08-05 02:16:08 +00:00
Guido van Rossum c0b618a2cc Quickly renamed the last directory. 1997-05-02 03:12:38 +00:00
Guido van Rossum 0969ad213d Better tuple hash function. 1996-12-16 17:55:46 +00:00
Guido van Rossum d266eb460e New permission notice, includes CNRI. 1996-10-25 14:44:06 +00:00
Guido van Rossum 441e4ab802 new debugger symbol names 1996-05-23 22:46:51 +00:00
Guido van Rossum 055968c068 better err checks in resizetuple 1995-08-04 04:05:10 +00:00
Guido van Rossum 6f9e433ab3 fix dusty debugging macros 1995-03-29 16:57:48 +00:00
Guido van Rossum 5fe605889a a few peephole optimizations 1995-03-09 12:12:50 +00:00
Guido van Rossum 6610ad9d6b Added 1995 to copyright message.
floatobject.c: fix hash().
methodobject.c: support METH_FREENAME flag bit.
1995-01-04 19:07:38 +00:00
Guido van Rossum 1d5735e846 Merge back to main trunk 1994-08-30 08:27:36 +00:00
Guido van Rossum a3d78fb268 * posixmodule.c: added set{uid,gid}.
* {tuple,list,mapping,array}object.c: call printobject with 0 for flags
* compile.c (parsestr): use quote instead of '\'' at one crucial point
* arraymodule.c (array_getattr): Added __members__ attribute
1993-11-10 09:23:53 +00:00
Sjoerd Mullender 615194a352 Fixed bugs in resizetuple and extended the interface.
Added ifdefs in stringobject.c for shared strings of length 1.
Renamed free_list in tupleobject.c to free_tuples.
1993-11-01 13:46:50 +00:00
Guido van Rossum 12d12c5faf * compile.[ch]: support for lambda()
* PROTO.h, mymalloc.h: added #ifdefs for TURBOC and GNUC.
* allobjects.h: added #include "rangeobject.h"
* Grammar: added lambda_input; relaxed syntax for exec.
* bltinmodule.c: added bagof, map, reduce, lambda, xrange.
* tupleobject.[ch]: added resizetuple().
* rangeobject.[ch]: new object type to speed up range operations (not
  convinced this is needed!!!)
1993-10-26 17:58:25 +00:00
Sjoerd Mullender 842d2ccdcd intobject.c: Save references to small integers, so that they can be
shared.  The default is to save references to the integers in
	the range -1..99.  The lower limit can be set by defining
	NSMALLNEGINTS (absolute value of smallest integer to be saved)
	and NSMALLPOSINTS (1 more than the largest integer to be
	saved).
tupleobject.c: Save a reference to the empty tuple to be returned
	whenever a tuple of size 0 is requested.  Tuples of size 1
	upto, but not including, MAXSAVESIZE (default 20) are put in
	free lists when deallocated.  When MAXSAVESIZE equals 1, only
	share references to the empty tuple, when MAXSAVESIZE equals
	0, don't include the code at all and revert to the old
	behavior.
object.c: Print some more statistics when COUNT_ALLOCS is defined.
1993-10-15 16:18:48 +00:00
Sjoerd Mullender a9c3c22c33 * Extended X interface: pixmap objects, colormap objects visual objects,
image objects, and lots of new methods.
* Added counting of allocations and deallocations of builtin types if
  COUNT_ALLOCS is defined.  Had to move calls to NEWREF down in some
  files.
* Bug fix in sorting lists.
1993-10-11 12:54:31 +00:00
Guido van Rossum 234f942aef * Added gmtime/localtime/mktime and SYSV timezone globals to timemodule.c.
Added $(SYSDEF) to its build rule in Makefile.
* cgensupport.[ch], modsupport.[ch]: removed some old stuff.  Also
  changed files that still used it...  And made several things static
  that weren't but should have been...  And other minor cleanups...
* listobject.[ch]: add external interfaces {set,get}listslice
* socketmodule.c: fix bugs in new send() argument parsing.
* sunaudiodevmodule.c: added flush() and close().
1993-06-17 12:35:49 +00:00
Guido van Rossum 9bfef44d97 * Changed all copyright messages to include 1993.
* Stubs for faster implementation of local variables (not yet finished)
* Added function name to code object.  Print it for code and function
  objects.  THIS MAKES THE .PYC FILE FORMAT INCOMPATIBLE (the version
  number has changed accordingly)
* Print address of self for built-in methods
* New internal functions getattro and setattro (getattr/setattr with
  string object arg)
* Replaced "dictobject" with more powerful "mappingobject"
* New per-type functio tp_hash to implement arbitrary object hashing,
  and hashobject() to interface to it
* Added built-in functions hash(v) and hasattr(v, 'name')
* classobject: made some functions static that accidentally weren't;
  added __hash__ special instance method to implement hash()
* Added proper comparison for built-in methods and functions
1993-03-29 10:43:31 +00:00
Guido van Rossum bab9d03855 Copyright for 1992 added 1992-04-05 14:26:55 +00:00
Guido van Rossum 7c36ad7f44 New function gettupleslice(v, i, j). 1992-01-14 18:45:33 +00:00
Guido van Rossum 49e85146e2 printobject now returns an error code
Remove superfluous err_nomem() call
,
1991-06-07 22:59:30 +00:00
Guido van Rossum b8393da8f8 Finally implement tuple*number. From now on all sequence types
must (pretend to) support all operations except assignments;
if you don't want to support an operation you have to provide
a dummy function that raises an exception...
1991-06-04 19:35:24 +00:00
Guido van Rossum f70e43a073 Added copyright notice. 1991-02-19 12:39:46 +00:00
Guido van Rossum 3f5da24ea3 "Compiling" version 1990-12-20 15:06:42 +00:00
Guido van Rossum 2a9096b5f9 New errors. 1990-10-21 22:15:08 +00:00
Guido van Rossum 85a5fbbdfe Initial revision 1990-10-14 12:07:46 +00:00