[Fontconfig] Fontconfig performance question.
brushlst at pol.pl
Wed May 7 19:08:45 EST 2003
I've been profiling some KDE applications recently (namely Kmail, Konqueror
and Konsole) using valgrind.
I've noticed that significant amount of startup time is devoted to Fontconfig
F.e. for Konsole (i've started it and quited immediately to measure just the
a call to FcInit consumes 33.49% of the total execution time.
FCinit calls 5 different functions but 4 of them are neglible only one stands
out: FcLoadConfigAndFonts - it takes 33.49% (=it does most of the job in
So i dig further:
Again, one call inside FcLoadConfigAndFonts consumes most of the time:
It's FcConfigBuildFonts and inside of it, FcDirScan takes 32.78% of total
And we are close to the final now: in FcDirScan the function FcDirCacheReadDir
takes 32.78% of total time (total time means total application execution
And inside this function there is a lot of action but onfortunately i'm
missing debugging symbols so i can not see all the function names but the
first function calls mostly
FcNameParse who is responsible for 22.84% of total execution time..
If you are interested then i can send you my valgrind output files so you can
all see it yourself.
But something is wrong with the fontconfig in the sense that it still takes
too long just to load config at the startup despite the cache.
Can't we just dump the serialized binary config structures from the memory to
disk and then only compare file dates and do the parsing only when necesary?
Or maybe a daemon holding configuration in the memory and serving it to
What do you think about it guys? 1/3 of the startup time for KDE application
is certainly worth the effort (and all GTK2 apps will also benefit).
congratulations for a great project by the way,
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