Re: Floating point in pango

[Jorn Baayen <jorn openedhand com>]

Hi,

On Wed, 2006-07-12 at 06:13 -0700, Carl Worth wrote:
> On Tue, 11 Jul 2006 12:04:38 +0300, Jorn Baayen wrote:
> > >
> > > What do you exactly mean by 30% slowdown?  How was that measured?
> > 
> > Timing the drawing of text using GTK 2.6 vs GTK 2.8, by connecting two
> > signal handlers to the 'expose-event' of a GtkLabel, one before and one
> > after the default handler, and timing the difference. The difference is
> > about 30% higher using GTK 2.8. I attach the code used.
> > (All this on ARM)
> 
> So has anyone done any profiling of this kind of thing yet?

Yeap. Sorry it took me a while to get back.

I have uploaded oprofile profiles of the test program I posted earlier
to:

http://www.o-hand.com/~jorn/pango-benchmarks/

There are profiles against both GTK+ 2.6.8 as well as 2.8.18. For both
pango 1.10.0 and glib 2.10.3 were used.

Some things that jumped to my eye:

 o Using GTK+ 2.8.18 the testcase runs about 30% faster.

 o pango_renderer_draw_layout_line() jumped from 2.3% to 8.7% in the
   pango profile between 2.6.8 and 2.8.18.

 o Why 7% of the time spent in GTK+ spent in
   _gtk_style_peek_property_value() using 2.8 ?


Thanks,

Jorn


> 
> That's what's needed next before we start guessing about things like
> API changes for cairo, etc.

> 
> -Carl
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