On Tue, 18 Dec 2001, Peter Surda wrote:
> On Tue, Dec 18, 2001 at 03:07:29PM +0100, Andre Werthmann wrote:
> > I have a laptop with a SiS630 chipset and use XFree86 4.1 (sis driver
> with
> > the vesafb hack).
> > When I play a dvd in windowed mode (720x576) with xine and I use
> XVideo
> > the cpu(1.1Ghz P3) is utilized at 66% while playing with XShm the cpu
> is
> > utilized only at 31% !
> > (the same with mplayer)
> >
> > This effect is the same at all colordepths (16bpp and 24bpp).
> >
> > I thought Xv should take the strain off the cpu a bit...
> >
> >
> > Anyone has an idea what may cause the problem ?
> It is because the driver uses memcpy for transferring of the data. The
> correct
> way to solve this is to add dma support. In current cvs XF86 r128 does
> this so
> it can be used as a reference implementation.
>
That's silly. Plenty of other drivers do this without DMA
and have large performance increases over XShmPutImage - typically a
factor of two savings with scaling for free. In the worst case
XvShmPutImage should be comparable to XShmPutImage. Absense of
DMA capability is not the problem.
Mark.
_______________________________________________
Xpert mailing list
[EMAIL PROTECTED]
http://XFree86.Org/mailman/listinfo/xpert
