Re: [xsl] Optimizing XSLT iteration

["Sujata Gohad" <sgohad@xxxxxxx>]

Hi David,

Thanks for your insights.

> I doubt there is much you can do within xslt, since your example program
> is essentially doing nothing other than iterating through the locus
> elements (and outputtig the string value if a few attributes) I wouldn't
> have been surprised if greater than 80% of the time is in that
> enumeration.


Does outputting the string value have any effect on the performance?
Is there any way to collectively read all the values and then output.
This might sound naive a question, but I am considering just about
every possibility. :-)


> externally to xslt there may be things you can do, saxon works with
> several different XML models, but some are faster than others so if your
> input is built by saxon to its native tiny tree model things may be
> faster than when you give saxon a DM.


I am dealing with documents that are 20-60MB in size and have a number
of sequences as shown in my example xml. As you can imagine, iterating
through those many takes huge amounts of time.

What would be the best way to attack the issue? Is there a good
reference/article on this topic?

I have tried using Saxon with TinyTree, Xalan, MSXML6 and Altova.

On a Intel Core Duo with 2Gig memory, Saxon, Xalan would run out of heap space.

Altova could handle files only upto 40MB.

MSXML successfully dealt with all file sizes, but the 60MB file took
over 25 minutes to transform.

Saxon, for the file sizes it could do, it was at least 1.2-1.3 times
faster than MSXML.


>
> So if speed is an issue, you may want to look to how your input tree is
> built...
>

More hints in this area would be appreciated.


Many thanks,
- Sujata