Is there some way I can get off this mailing list, which has nothing at all to do with me?
On Thu, Jul 21, 2022 at 4:34 AM Davide Capodaglio < davide.capodag...@axelsw.it> wrote: > Hi Roger, > I already tried to compile xerces with ICU but it makes no difference at > all. > However on Windows platform also MSXML internally converts all to UTF-16 > (because everything on Windows nowadays uses Unicode with wchar_t=UTF-16), > and Xerces uses internal Windows API, but I see more than a 2x slowdown > then MSXML for a just a load of a document. > > But, as I said my big performance problem is with XQilla queries. > > Also in my benchmarks of the selectNodes() I am already specifying u16 > literals. > > I will try to use valgrind, but I have very few hopes at the moment... > > Thanks > Davide > > > > -----Messaggio originale----- > > Da: Roger Leigh <rle...@codelibre.net> > > Inviato: giovedì 21 luglio 2022 01:49 > > A: c-users@xerces.apache.org > > Oggetto: RE: Xerces-C++ and XQilla bad performance > > > > Hi Davide, > > > > I would suggest running your program under valgrind with kcallgrind and > > profiling the execution. When you view the results, you should see where > > the hotspots are. > > > > Based upon my previous profiling experiments, I suspect you'll find that > over > > 50% of the runtime is spent in the transcoder doing UTF-8 to UTF-16 > > conversions (and vice-versa). > > > > If this is the case, I would suggest trying a different transcoder and > > reprofiling. This may be where the Windows performance difference lies. > > An additional optimisation would be to reduce the number of conversions. > > For example, if you are repeatedly transcoding a UTF-8 string for use > with a > > function requiring UTF-16, you can cache the conversion. Or use char16_t > > with u16 string literals. At the expense of portability with older > compilers. > > > > Kind regards, > > Roger > > > > > -----Original Message----- > > > From: Davide Capodaglio <davide.capodag...@axelsw.it> > > > Sent: 20 July 2022 14:44 > > > To: c-users@xerces.apache.org > > > Subject: Xerces-C++ and XQilla bad performance > > > > > > Is there any known way to optimize the performance of Xerces-C++ and > > > XQilla in both loading and XPath execution? > >
