From kde-devel Sat Apr 13 19:09:59 2002 From: Lubos Lunak Date: Sat, 13 Apr 2002 19:09:59 +0000 To: kde-devel Subject: Re: Question - using --enable-fast-malloc=full X-MARC-Message: https://marc.info/?l=kde-devel&m=101872520332307 On so 13. duben 2002 04:23, Marc Espie wrote: > In article <3CB60510.7080905@yahoo.com> you write: > >Lubos Lunak wrote: > >>On Thu 11. April 2002 17:36, Pavel Troller wrote: > >>>Hi! > >>> I recently tried the configure option noted in the subject and it's > >>>really a sort of Turbo Switch (TM)! At least system startup speed and > >>>konqueror/khtml are really faster now! > >>> What I'm asking: this option is present in kdelibs. After recompiling > >>>kdelibs with it will the fast malloc be used by all the packages > >>>automatically, or should they be recompiled first to use it ? > >>> With regards, Pavel > >>> Troller > >> > >> Just rebuilding libkdecore is enough. > > > >What is the disadvantage of that compile option? > >Cheers > >F@lk > > Doesn't buy you anything on some systems, either because they don't support > threads, or they have another malloc entirely. > > In fact, this is fairly tied to glibc. If you don't have the glibc, it uses No, it's not, --enable-fast-malloc=full should work on all systems, for which a spinlock implementation is available (right now only for x86, but I can find and add more if there's interest). Glibc is needed only when =full is not given, and using --enable-fast-malloc without =full makes sense only one wants to have it configurable at runtime (e.g. for debugging, or when one doesn't trust it entirely ;) ). > its own malloc. And some systems may have another malloc, that works faster > than that specific malloc... That's the point, using own implementation of malloc (and the fastest one I could find - I actually doubt there can be a faster one). > > This is what I experienced on OpenBSD. fast-malloc is not any faster than > the default malloc, and it's even a bit slower. Not in my small test. http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdlib/malloc.c needed almost double the time kdecore/malloc needed (hopefully the same conditions, even though maybe I missed some important option for openbsd malloc). Looking at the source also doesn't make me think it's the fastest malloc in the world. -- Lubos Lunak llunak@suse.cz ; l.lunak@kde.org http://dforce.sh.cvut.cz/~seli >> Visit http://mail.kde.org/mailman/listinfo/kde-devel#unsub to unsubscribe <<