Re: [xml] Re: Thread-safety of XSLT contexts with shared dictionaries

[Daniel Veillard <veillard redhat com>]

On Fri, Jan 21, 2005 at 05:54:13PM +0000, Gary Coady wrote:
> Daniel Veillard wrote:
> >  Applied, seems to give around 2% performances loss in kind of worse
> > case tests but it's bearable since it an exact solution to a nasty to debug
> > race otherwise.
> >
> >  before (best of 5 tests)
> >
> > test64:~/XML/xstc -> time nist-test.py -s -b .
> > Ran 5430 of 5430 tests: 500 failed 48 unimplemented
> >
> > real    0m3.301s
> > user    0m2.879s
> > sys     0m0.422s
> > test64:~/XML/xstc ->
> >
> >  after (best of 5 tests)
> >
> > test64:~/XML/xstc -> time nist-test.py -s -b .
> > Ran 5430 of 5430 tests: 500 failed 48 unimplemented
> >
> > real    0m3.358s
> > user    0m2.951s
> > sys     0m0.407s
> > test64:~/XML/xstc ->
> >
> >  Commited. But it would be interesting to see if the global lock one 
> > would lead to less performance losses on non threaded applications, could
> > you send again the first patch but as an attachment ?
>
> Daniel, thanks for committing the change.
>
> I'm attaching the first patch. Well, mostly the first patch, with some 
> extra code to make sure that a failure to initialize the mutex is 
> recognised.

  I now get (again best of 5 runs) 

t64:~/XML/xstc -> time nist-test.py -s -b .
Ran 5430 of 5430 tests: 500 failed 48 unimplemented

real    0m3.309s
user    0m2.908s
sys     0m0.401s
test64:~/XML/xstc -> 

  We are nearly back to the same performances of unsafe code :-)

  I think creating the lock is more costly than expected, and that
it's a better solution for most users then. We are back basically
to the same level of performances on Linux/RHEL/NPTL, so I commited
that version overriding the previous one. If someone one day experience
too much contention 1/ the second patch is still archived 2/ the parser
is probably not the place where they will loose the most cycles waiting.

  thanks again,

Daniel
-- 
Daniel Veillard      | Red Hat Desktop team http://redhat.com/
veillard redhat com  | libxml GNOME XML XSLT toolkit  http://xmlsoft.org/
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