[gcompris-devel] Performance issues

[Bruno Coudoin]

Le mercredi 03 octobre 2007 à 08:12 +0300, Terje Bergström a écrit :
> On 10/1/07, Bruno Coudoin <bruno.coudoin at free.fr> wrote:
>         Le dimanche 30 septembre 2007 à 13:29 +0300, Terje Bergström a
>         écrit :
>         > One thing I notice is that the plugins are scanned every
>         time I go
>         > back to
>         > menu. So I'm getting error messages about missing python,
>         and missing 
>         > libshapegame.so often. Perhaps this scanning is making
>         actions slow?
>         If I remember the scanning is done once but each time we get
>         an activity
>         for which we don't have a plugin we probably try again.
> 
> I now filtered out all python activities. One thing that I immediately
> noticed was that gcompris gave the same errors as before, i.e.
> couldn't load activity xxx.xml, even though xxx.xml didn't exist
> anymore. I was pretty confused about this. Anyway, in the end I
> noticed that this was due to database .config/gcompris/ in still
> referring to the activities that don't exist anymore. I guess I have
> to add a post-install script to remove that database when a new
> activities package is installed. Ubuntu packages don't delete that
> file, either, so they might end up with same problem. 

Yes, there is a cache in an sqlite database.
You can manually run gcompris --reread-menu

The database includes the GCompris release and we refresh it if the
running version doesn't match the database. There are no post install
script to do, the issue is only for developers.

> I removed that file, disabled all sounds to make sure they don't
> affect performance, and this time when I'm changing between activity
> menus (like from the second with keyboard and mouse activities to the
> first with puzzle activities), I still get more than three seconds of
> lag. The lag is there also when I click on "exit" before the
> confirmation query pops up, or when I click on preferences and before
> preferences window opens.

Perhaps it's a canvas refresh issue. I don't know. You can try to locate
a slow location and add a printout in the console to try to determine
better where the delay comes from.

>  The news is that during those three seconds plus there are absolutely
> no debug outputs. Does this mean that those three seconds are spent
> building the canvas? I know absolutely nothing about gnomecanvas, so
> I'm not sure if I'm using the correct term here. 

Yes, perhaps a refresh issue. The canvas if just a library that let us
organize items graphically. It's not very efficient in term of speed but
easier to program.

> By the way, I have released the first port of gcompris 8.4 for maemo.
> There are still problems, but the list is much shorter than the list
> of problems I had with my earlier port.

Great news.


-- 
Bruno Coudoin
http://gcompris.net Free educational software for kids
http://toulibre.org Logiciel Libre à Toulouse