Message 66628 - Python tracker

Author	hanselda
Recipients	hanselda
Date	2008-05-11.13:32:15
SpamBayes Score	0.226393
Marked as misclassified	No
Message-id	<1210512738.34.0.315015103661.issue2818@psf.upfronthosting.co.za>
In-reply-to

Content
when use xml.dom.pulldom module to parse a large xml file, if all the information is saved in one xml file, the module can handle it in the following way without construction the whole DOM: events = xml.dom.pulldom.parse('file.xml') for (event, node) in events: process(event, node) But if 'file.xml' contains some large external entities, for example: <!ENTITY file_external SYSTEM "others.xml"> <body>&file_external;</body> Then using the same python snippet above leads to enormous memory usage. I did not perform a concrete benchmark, in one case a 3M external xml file drained about 1 GB memory. I think in this case it might be the whole DOM structure is constructed.

when use xml.dom.pulldom module to parse a large xml file, if all the 
information is saved in one xml file, the module can handle it in the 
following way without construction the whole DOM:

events = xml.dom.pulldom.parse('file.xml')
for (event, node) in events:
    process(event, node)

But if 'file.xml' contains some large external entities, for example:

<!ENTITY file_external SYSTEM "others.xml">
<body>&file_external;</body>

Then using the same python snippet above leads to enormous memory 
usage. I did not perform a concrete benchmark, in one case a 3M 
external xml file drained about 1 GB memory. I think in this case it 
might be the whole DOM structure is constructed.

History
Date	User	Action	Args
2008-05-11 13:32:18	hanselda	set	spambayes_score: 0.226393 -> 0.226393 recipients: + hanselda
2008-05-11 13:32:18	hanselda	set	spambayes_score: 0.226393 -> 0.226393 messageid: <1210512738.34.0.315015103661.issue2818@psf.upfronthosting.co.za>
2008-05-11 13:32:17	hanselda	link	issue2818 messages
2008-05-11 13:32:16	hanselda	create