Is your usage pattern over the constructed tree likely to be a lazy prefix traversal?  If so, then HaXml supports lazy construction of the parse tree.  Some plots appear at the end of this paper, showing how memory usage can be reduced to a constant, even for very large inputs (1 million tree nodes): http://www.cs.york.ac.uk/plasma/publications/pdf/partialparse.pdf Regards, Malcolm On 20 Feb, 2014,at 11:30 AM, Christian Maeder wrote: Hi, I've got some difficulties parsing "large" xml files (> 100MB). A plain SAX parser, as provided by hexpat, is fine. However, constructing a tree consumes too much memory on a 32bit machine. see http://trac.informatik.uni-bremen.de:8080/hets/ticket/1248 I suspect that sharing strings when constructing trees might greatly reduce memory requirements. What are suitable libraries for string pools? Before trying to implement something myself, I'ld like to ask who else has tried to process large xml files (and met similar memory problems)? I have not yet investigated xml-conduit and hxt for our purpose. (These look scary.) In fact, I've basically used the content trees from "The (simple) xml package" and switching to another tree type is no fun, in particular if this gains not much. Thanks Christian _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

On 20/02/14 11:30, Christian Maeder wrote:

Hi,

I've got some difficulties parsing "large" xml files (> 100MB). A plain SAX parser, as provided by hexpat, is fine. However, constructing a tree consumes too much memory on a 32bit machine.

see http://trac.informatik.uni-bremen.de:8080/hets/ticket/1248

I suspect that sharing strings when constructing trees might greatly reduce memory requirements. What are suitable libraries for string pools?

Before trying to implement something myself, I'ld like to ask who else has tried to process large xml files (and met similar memory problems)?

I have not yet investigated xml-conduit and hxt for our purpose. (These look scary.)

In fact, I've basically used the content trees from "The (simple) xml package" and switching to another tree type is no fun, in particular if this gains not much.

Thanks Christian _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

HXT will not work for you, you will run out of memory on files ~30MB. I don't know about xml-conduit, I'd love to hear how it goes if you try it. -- Mateusz K.