Tons of questions. And some patches

Alexander Neundorf neundorf at kde.org
Sun Jan 25 19:26:43 GMT 2004


On Sunday 25 January 2004 15:55, Frans Englich wrote:
> On Saturday 24 January 2004 21:07, Alexander Neundorf wrote:
> > On Saturday 24 January 2004 15:27, Frans Englich wrote:
> > > Below is a pile of questions and tiny patches. If it was a bad idea
> > > grouping it all in one mail I will split it up in smaller ones(or some
> > > other better way).
> > >
> > > * AFAICT there is clear advantages of having desktop files in a XML
> > > format. Why is it not so? Speed issues?
> >
> > At least partly, yes.
> > When starting a kde app a whole bunch of desktop files is read (I think
> > it was something around 10 or so, maybe even more)
> > The desktop file reading in kde is highly optimized, xml will be slower.
>
> AFAIK: If you launch an app by clicking on it's .desktop file, that desktop
> file will be parsed, with appropriate actions.

Start a app with strace to see what happens.

The global kderc is parsed, the user kderc file is parsed. The global app 
config file is parsed, the user app config file is parsed. Serveral icon 
description files are parsed.
I think there were more files, but you see it's more than one.
Ok, these files aren't .desktop, but they are also read by KConfig.

> But all other lookups, as
> well as if you start it from the KMenu, are done via the ksycoca database
> and that's explains why it's so fast as well as why .desktop files very
> seldom needs to be parsed.. The actual parsing only happens when ksycoca
> updates its db or when a .desktop file is ("explicitly") run. Well, I
> really don't know how this works. Is this voodoo documented somewhere?
> And if that's the case, the "runtime" speed impact would not be noticeble,

The startup time impact is noticable. I did a lot of measurements with my old 
K6/200 some time ago. On slow boxes it does matter.

> AFAICT. In either case, is it really a big deal between parsing an xml file
> and a .desktop file?

Yes. 

Bye
Alex
-- 
Work: alexander.neundorf at jenoptik.com - http://www.jenoptik-los.de
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