Re: [Dri-users] Benchmarking xv (was: colours lost in movies)

[Felix <fx...@gm...>]

Am Montag, den 10.01.2005, 15:26 +0100 schrieb Zirzlaff, Torsten:
> Hi.
>=20
> Is it possible to benchmark the use of DMA for XV?
>=20
> I have the feeling, that with the feature of using DMA
> for xv that performance is lost on my system. I do have
> some strange behaviour with DMA resulting in heavy system
> workload, but I want to test it against xv, since with the
> current cvs-build (yesterday) the playback of large MPEG-4
> movies got slow compared to a previous snapshot where I had
> no problems at all.

Depending on the driver you're using the CPU usage may be a bad
indicator. I saw some busy waiting for Vsync in the Savage Xv code for
example. OTOH if using DMA doesn't get rid of busy waiting it may have
no positive effect at all on a reasonably fast CPU. Basically you spend
the same time waiting with DMA or doing color space conversions without
DMA.

>=20
> TIA
>=20
> 	Torsten

--=20
| Felix K=FChling <fx...@gm...>                     http://fxk.de.vu |
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