Java and XSLT heap space problem

imshriram · January 31st, 2012, 04:48 AM

Hello XSL masters,
I am calling XSL from java (saxon). I am using an input file of size 200 MB. When i run the transformer, I get the exception:

Code:

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
	at com.icl.saxon.tinytree.TinyDocumentImpl.appendChars(TinyDocumentImpl.java:174)
	at com.icl.saxon.tinytree.TinyBuilder.characters(TinyBuilder.java:224)
	at com.icl.saxon.output.ProxyEmitter.characters(ProxyEmitter.java:100)
	at com.icl.saxon.om.Stripper.characters(Stripper.java:201)
	at com.icl.saxon.ContentEmitter.flush(ContentEmitter.java:220)
	at com.icl.saxon.ContentEmitter.endDocument(ContentEmitter.java:75)
	at com.icl.saxon.aelfred.SAXDriver.parse(SAXDriver.java:334)
	at com.icl.saxon.om.Builder.build(Builder.java:265)
	at com.icl.saxon.Controller.transform(Controller.java:977)
	at com.myCompany.transformer.FunctionTransformer.myTransformer(FunctionTransformer.java:95)

I tried increasing the heap memory but of no use. What should I do to avoid this exception?

mhkay · January 31st, 2012, 05:31 AM

You are using a very old version of Saxon (the 6.x branch) and the first thing I would do would be to move to an up to date version (the current version is 9.4). This won't necessarily solve the problem on its own, but at least it will make it possible to offer some support.

Recent Saxon releases have the option -tree:tinyc which uses the TinyTree model with extra compression, which may make a difference.

For a 200Mb input document, you should be able to do the transformation if you allocate 1Gb of heap space, or 2Gb to be safe (the expansion factor depends on the nature of the data. You didn't say how much you actually allocated.

If that doesn't work, or if the source document gets any bigger, you could look at some of the facilities offered in Saxon-EE such as streaming and document projection to see if they help.

Note that for Saxon-specific problems, it's best to use the saxon-help list on SourceForge. Asking here, it's hit-or-miss who happens to visit the forum on any given day.

imshriram · February 1st, 2012, 01:02 AM

Thank you so much Kay.

Increasing the size to 1GB helped.

I will bear in mind to post to saxon forums on questions related to saxon.

My voice to move to saxon EE or atleast saxon 9 is not getting heard. Hence stuck with older versions. I am hoping for the best in the upcoming months.