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Re: much faster XPath queries with XT



Hi,

Fri, 05 May 2000 Dongwook Shin wrote:
>I also tested Xalan Xpath on my Pentium II 448Mhz with 256MB RAM.
>The query took around 3 sec in DOM mode.

Did you run the query on in-memory DOM or did you use the ozone PDOM?
B/c 3 sec for ozone PDOM would be great.

>I think the inefficiency
>of Xalan XPath arises from its brute force execution plan. It starts
>from the top-level step, gathering all the context nodes and switching
>to the next level and so on. It is extremely inefficient when you use
>"//" since it tries to collect all the descendant nodes as possible
>context nodes of the next step.

Yes. Benchmarking with absolute XPathes result in comparable values
for both implementations.

>I don't know how much XT is fast. But you can do benchmarking
>with my XRS system that has shakespare colleciton as the Web
>demonstration at: http://dlb2.nlm.nih.gov/~dwshin/xrs.html.

The problem I see is not-100%-conformance to the W3C XPath WD.

Regards,
Lars
--
________________________________________________________________
Lars Martin                         mailto:lars@softwarebuero.de
softwarebuero m&b (SMB)              http://www.softwarebuero.de