Kernel scheduling algorithm and X.Org performance

Dmitry M. Shatrov erdizz at
Fri Sep 2 07:45:25 PDT 2005

В Птн, 02/09/2005 в 15:10 +0200, Olivier Galibert пишет:
> On Fri, Sep 02, 2005 at 05:34:26PM +0400, Dmitry M. Shatrov wrote:
> > As I know, unlike Qt, Gtk+ queues frequent expose events
> > and lets the application deal with one large expose than a dozen of smaller ones.
> > It is hard for developers of nontrivial graphics programs to adopt to this
> > (as it was once hard for me). Did you ever notice how list scrolling lags in
> > Gtk+, especially when you use a theme with bitmap-tiled background?
> > (something that does not happen in Qt), or how badly Evince PDF viewer
> > (at least its earlier versions, I don't have the most recent one)
> > handles scrolling compared to kpdf?
> Errr, what has scrolling to do with expose events?  Are the toolkits
> designers doing a round-trip with the X server just for the fun of it?
>   OG.

Simple. When you implement a custom widget class you handle drawing
operations in an expose-event handler. When then you embed you widget in
a scrolling container, the expose-event handler of the custom widget is
called to handle scrolling. Gtk+ does its best to limit the amount
expose events delivered to the widget. That's how I see it..

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