Please remember that org.apache.xml.dtm.ref.DTMBaseTraversers and 
org.apache.xml.dtm.ref.DTMBaseIterators are also set up to use indexing; 
the xpath.axes package is only the tip of the iceberg.


It's perfectly possible that this code isn't actually being invoked, 
depending on what methods are called. We should check into this. But in 
that case the question is a larger one: whether we should eliminate 
indexing (as you suggest) or use it much more intensively (as was the 
original intent). 

Determining which of those paths is preferable may not be trivial. 
Remember that the smoketest is emphatically not made up of typical 
stylesheets and its performance characteristics may bear little or no 
resemblence to those of  real-world applications. That's not its purpose; 
it exists to warn us when we've broken something or when a change _might_ 
have unexpected performance implications.

As we've discussed, it's not hard to enable/disable indexing, so if 
someone is feeling ambitious they could start investigating this with a 
more realistic set of testcases. And we should definitely check whether 
indexing is currently being used everywhere it should be.

______________________________________
Joe Kesselman  / IBM Research

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