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When I need to deal with huge XML files, I use Perl's XML::Parser in "stream" mode. It's blazing fast, but I have to admit, the code isn't very pretty. There's also XML::LibXML::SAX<http://search.cpan.org/dist/XML-LibXML/lib/XML/LibXML/SAX.pod>, but I can't seem to find any substantive documentation on how this works. (If anyone has any sample code that uses this, I'd love to see it. Please e-mail me off-list as I don't want to de-rail this thread.) Teemu's suggestion about XML::LibXML::Reader is definitely worth considering. I've never clocked it against XML::Parser, but it seems like it *should* be fast. And as Teemu demonstrated, it allows you to write nice compact code. Ron On Fri, Jun 8, 2012 at 2:36 PM, Kyle Banerjee <[log in to unmask]>wrote: > I'm working on a script that needs to be able to crosswalk at least a > couple hundred XML files regularly, some of which are quite large. > > I've thought of a number of ways to go about this, but I wanted to bounce > this off the list since I'm sure people here deal with this problem all the > time. My goal is to make something that's easy to read/maintain without > pegging the CPU and consuming too much memory. > > The performance and load I'm seeing from running the files through LibXML > and SimpleXML on the large files is completely unacceptable. SAX is not out > of the question, but I'm trying to avoid it if possible to keep the code > more compact and easier to read. > > I'm tempted to streamedit out all line breaks since they occur in > unpredictable places and put new ones at the end of each record into a temp > file. Then I can read the temp file one line at a time and process using > SimpleXML. That way, there's no need to load giant files into memory, > create huge arrays, etc and the code would be easy enough for a 6th grader > to follow. My proposed method doesn't sound very efficient to me, but it > should consume predictable resources which don't increase with file size. > > How do you guys deal with large XML files? Thanks, > > kyle > > <rant>Why the heck does the XML spec require a root element, > particularly since large files usually consist of a large number of > records/documents? This makes it absolutely impossible to process a file of > any size without resorting to SAX or string parsing -- which takes away > many of the advantages you'd normally have with an XML structure. </rant> > > -- > ---------------------------------------------------------- > Kyle Banerjee > Digital Services Program Manager > Orbis Cascade Alliance > <[log in to unmask]>[log in to unmask] / 503.999.9787 >