[Intel-gfx] Advantages of CreateSolidFill as src for CompositeText?

[Chris Wilson]

On Tue, 15 Jun 2010 16:08:45 +0200, Clemens Eisserer <linuxhippy at gmail.com> wrote:
> With 2.11.901 everything seems to be fine, but I wonder - what is the
> preferred way to do this across different drivers (EXA)?
> I remember I decided to go with the 1x1 pixmap because EXA back then
> didn't like solid fills with alpha value, and 1x1 pixmaps performed
> quite well everywhere.

If it did not trigger fallbacks in the current EXA drivers, I would
recommend going with SolidFill instead of 1x1 pixmaps (and similarly would
enable them in Cairo).

Using SolidFill (PineView):
36000000 trep @   0.0008 msec (1290000.0/sec): Char in 80-char aa line (Charter 10)
32000000 trep @   0.0008 msec (1270000.0/sec): Char in 80-char rgb line (Charter 10)
Using 1x1R (PineView):
32000000 trep @   0.0008 msec (1250000.0/sec): Char in 80-char aa line (Charter 10)
32000000 trep @   0.0008 msec (1230000.0/sec): Char in 80-char rgb line (Charter 10)

Whilst that only indicates a 4% throughput improvement in a pretty ideal
scenario, for a more normal application there is also a reduction in the
volume of X traffic, as creating a SolidFill is much cheaper than creating
and filling a 1x1R. Also the above benchmark does not reveal the cost of
immediately using a 1x1R as a solid colour after creation, as that incurs
the overhead of a readback currently.
-ickle

-- 
Chris Wilson, Intel Open Source Technology Centre