Re: Re: Re: xsl:for-each evaluator?

"Michael Kay" <mhk@xxxxxxxxx> wrote in message
news:001b01c33065$aafbe190$6401a8c0@xxxxxxxxxx
> >
> > One *cannot know* if a program will terminate -- unless this
> > property has a strict proof.
>
> That's true in general. But there is a large class of stylesheets for
> which you can prove termination: anything that only selects downwards
> will finish in finite time if given a finite source document.

Yes, definitely.


>
> It's not clear what the OP was asking for, but I don't think he wanted
> static analysis, just some kind of instrumentation.
>
> There's tracing in Saxon, including a tool that gives you a trace with
> timing information, and a stylesheet for analyzing the trace output.
> Unfortunately the timing information you can get from Java is very
> coarse-grained, so it's of limited use.

>From my observation with Saxon 6.5 I get the stylesheet execution time
reported as at least 120 milliseconds even for the simplest transformations.
Times from other XSLT processors -- MSXML: from a fraction of a millisecond
to 3-5 milliseconds, xsltProc: 10 milliseconds, JD: 50 milliseconds.

But Saxon doesn't seem to perform slower than xsltProc or JD.


It is nice to have built-in tracing and profiling capabilities. On the other
side, using extension functions that read the time may be problematic, as
reading the time is a side effect (e.g. calls to such extension functions
may be rearranged or even eliminated by lazy evaluation and optimization).



=====
Cheers,

Dimitre Novatchev.
http://fxsl.sourceforge.net/ -- the home of FXSL




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