Messages in this thread | | | Date | Tue, 24 Feb 1998 17:40:37 +0000 | From | Torgeir Veimo <> | Subject | [OFFTOPIC] Was: Re: GGI, EGCS/PGCC, Kernel source |
| |
Nate Tuck: > If you can read that data out of memory and write it directly to the > graphics hardware, this "only" requires 640 MB/s of CPU bandwidth and 320 > MB/s of > memory bandwidth. Write it to a DMA buffer instead, and now you are at 640 > MB/s of CPU bandwidth and 960 MB/s of memory bandwidth. Add a copy from > the server's input queue to the DMA buffer and you are at ~1.3 GB/s of CPU > bandwidth and 1.6 GB/s of memory bandwidth.
The way the userland driver talks to the card is either through a ping-pong buffer, through mmio, or through dma if the card can handle it. More and more cards do handle dma every day.
I think I should go back to coding again and present my case when I can show that it works and how it speeds up things.
Alan Cox: > Hopefully I can spend an evening armwaving with GGI folks (Geert you going to be there ?) > and see what I can learn
This would be very nice.
--
Torgeir Veimo, Vertech AS,
email: Torgeir.Veimo@vertech.no, mobile: 90673881, office: +47 55563755
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu
| |