I wonder why those haven't got traction with things like Mozilla though. Presumably -someone- would at least have looked at them if they're that big a win?

I meant "DOM" as in the general "tree in memory" data structure. You did find an implementation that uses about 1/3 the memory of some of the piggier ones, though.

closer to 1/5th.

also, in actual use -> those are peak values, so while libxml will hog the memory until the DOM is freed, the streaming style parsers hold on to the smaller amount of memory for a shorter time.

In the problem above, I did try using the SAX parser that the WebLogic-JVM "factory factory factory" returned, but the element text was about 2 MB, and it wanted to return it in pieces by repeatedly firing the event handler.

Manually finding the index of the open/close elements and doing a substring to get the element text was SO incredibly much faster and smaller, albeit something that only worked for a VERY specific situation.