X performance problems with Matrox G550

Michel Dänzer michel at daenzer.net
Thu Nov 4 21:11:02 PST 2004

On Thu, 2004-11-04 at 11:13 +0000, Martin Ebourne wrote:
> On Thu, 2004-11-04 at 04:01, Michel Dänzer wrote:
> > Is direct rendering enabled? AGP doesn't come into play otherwise.
> Ah, now I didn't know that. It is definitely not enabled; the mga kernel
> module is not 64 bit clean so is not available on the Athlon64.
> So now I'd like to know if that will make the difference. If I port the
> mga module to amd64 will CRTC2 on the mga driver use AGP for blit
> operations?

>From your log it looks like the DRI wouldn't be enabled for CRTC2
anyway, and even if it was, I don't know if the mga driver would take
advantage of it for blits.

> One thing to note is that playback to a monitor on CRTC1 (which does use
> the BES) is at full rate and only using about 50% of the CPU (30% by X).
> This is without AGP but with write-combining. It has just as much data
> to transfer to the card (source is 720x576) as when running on the TV on
> CRTC2, but does it in less than half the CPU.

The YUV data is probably only 2 bytes per pixel.

Earthling Michel Dänzer      |     Debian (powerpc), X and DRI developer
Libre software enthusiast    |   http://svcs.affero.net/rm.php?r=daenzer

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