Memory leakage in SAX with exception

[pandreetto]

BPO	589149
Nosy	@loewis, @facundobatista

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = 'https://github.com/loewis'
closed_at = <Date 2004-11-09.00:25:03.000>
created_at = <Date 2002-07-31.15:02:10.000>
labels = ['expert-XML']
title = 'Memory leakage in SAX with exception'
updated_at = <Date 2004-11-09.00:25:03.000>
user = 'https://bugs.python.org/pandreetto'

bugs.python.org fields:

activity = <Date 2004-11-09.00:25:03.000>
actor = 'facundobatista'
assignee = 'loewis'
closed = True
closed_date = None
closer = None
components = ['XML']
creation = <Date 2002-07-31.15:02:10.000>
creator = 'pandreetto'
dependencies = []
files = []
hgrepos = []
issue_num = 589149
keywords = []
message_count = 7.0
messages = ['11765', '11766', '11767', '11768', '11769', '11770', '11771']
nosy_count = 4.0
nosy_names = ['loewis', 'nnorwitz', 'facundobatista', 'pandreetto']
pr_nums = []
priority = 'normal'
resolution = 'fixed'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue589149'
versions = []

[pandreetto]

Trying the following test:

#!/usr/bin/python

import sys,string,StringIO,traceback,time,gc
import xml.sax,xml.sax.handler
gc.set_debug(gc.DEBUG_SAVEALL)

class SimpleHandler(xml.sax.handler.ContentHandler):
    def __init__(self):
        pass

    def startElement(self,name,attrs):
        print 'start ',name

    def endElement(self,name):
        print 'end ',name

    def characters(self,content):
        print content

class SimpleErrorHandler(xml.sax.handler.ErrorHandler):
    def __init__(self):
        pass
        
    def fatalError(self,e):
        print e

myHandler=SimpleHandler()
myErrHandler=SimpleErrorHandler()
data='<test>something</>'
while 1:
    gc.collect()
    print len(gc.garbage)
    
    try:
        #xml.sax.parseString(data,myHandler,myErrHandler)
        xml.sax.parseString(data,myHandler)
    except Exception, e:
        sinfo=sys.exc_info()
	traceback.print_tb(sinfo[2],None)
    time.sleep(1)

it seems that lots of object remain uncollectable.
Using the SimpleErrorHandler the behaviour of gc is
good but a memory leakage still remain (4Kb every 30
seconds).
Tests run on i386 with debian/Linux (sid), python 2.1.3
(Build of July 29th).

Thanks

[loewis]

Logged In: YES
user_id=21627

Your analysis of this result is wrong. Instead, the result
shows that all objects *are* collectible, and that there is
merely cyclic garbage in case of a parser error - this
garbage *will* be collected, unless you explicitly ask the
GC to save it (which you do in your example).

[pandreetto]

Logged In: YES
user_id=551296

This is correct, it's my fault, but removing the
gc.set_dubug instruction the situation doesn't change. The
script is just a simple test, my trouble comes from a memory
leakage into SOAPpy module which uses another SAX-based
XML-parser.
If you think the problem doesn't depends on the python core,
please close this bug.
Thanks

[loewis]

Logged In: YES
user_id=21627

There might indeed have been a memory leak in Python 2.1.3,
but I cannot reproduce this with Python 2.2 or CVS-Python
anymore. Can you please try a more recent version and see
whether the problem goes away?

[nnorwitz]

Logged In: YES
user_id=33168

Paolo, can you confirm that this bug should be closed?

[pandreetto]

Logged In: YES
user_id=551296

With Python 2.3a1 (#2, Jan 1 2003, 18:44:29) there's no
memory leakage.
With Python 2.2.2 (#1, Jan 3 2003, 12:42:27) the problem
still occurs.
I've used debian (unstable) package for both versions of python.

[facundobatista]

Logged In: YES
user_id=752496

Fixed in 2.3, as the submitter posted.

. Facundo