You must be doing something wrong - XML::SAX is designed to process huge XML files. Show us your code and we'll show you the problem. Most likely you're building up a huge data-structure in your handler methods, but that's just one possibility.

Also, what XML::SAX parser are you using? The default (XML::SAX::PurePerl) has terrible performance and I wouldn't be at all surprised to find that it leaks memory. I suggest you try XML::SAX::ExpatXS, which is fast and has the best support for the complete SAX interface.

-sam