Messages in this thread |  | | Date | Fri, 7 Jun 1996 23:51:02 -0700 | From | "David S. Miller" <> | Subject | Re: Games |
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Date: Fri, 07 Jun 1996 22:41:31 -0600 From: Warner Losh <imp@village.org>
: It seems SGI found a performance problem with X. (Someone here : said the X protocol becomes a severe bottleneck on high-end : graphics hardware, but I'd heard about the CAD a long time ago.)
SGI has known about the bottleneck for years. Likely the CAD system uses some flavor of SGL or OpenGL. SGI has special hooks in their X server to give greater performance than X could deliver.
Also, as far as I know, ONYX boxes have video cards which implement the complete OPENGL library on the card in microcode. Else, another solution has been to allow local clients to mmap() areas of the frame buffer into their address space (this is what sundgadoom on the Sparcs do). This second approach doesn't work on video cards which lack direct access to a frame buffer, for example some eat only graphics commands and direct frame buffer changes are only possible via DMA reads/writes from main memory.
Later, David S. Miller dm@sgi.com
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