On Thu, Oct 24, 2002 at 12:36:20PM -0400, Owen Taylor wrote: | | I think the author is right that interesting things can be | done in the area of performance and X. As far as | particular problems that he identifies and solutions he | proposes... well, they certainly wouldn't be where I was | looking.
Definitely agreed. | Quick rundown of what I think _is_ interesting: | | - Store the full contents of all toplevels. Exposes are an | obsolete concept from when window contents were simpler and | graphics memory smaller. | | (You may want to discard information if memory gets tight, ... Unless you're willing to give a strong guarantee (e.g., roughly as strong as the one the VM system gives ordinary memory allocations) that all toplevels will have backing store, the apps still need to provide a mechanism to respond to exposures. Once you have that, it's been my experience that the overall performance of the system is maximized by giving up backing store and teaching the apps to redraw exposed regions efficiently. It may be that the toolkits need more work in the latter area. Historical note: Back when X11 was enjoying its first successes and I was working at Digital, I asked an SGI engineer how SGI machines were able to demonstrate such enormous text scrolling rates. He replied that they didn't bother to scroll; they had optimized the system for drawing, so they just re-drew the entire window for each frame. :-) | ... | - Improve the handling of offscreen memory management in | XFree86. Yes, that's crucially important for 3D as well. Most current 3D apps need a great deal of space for back buffer, depth buffer, textures, and scratch drawing areas. 64MB of graphics memory can be pretty tight in that environment, so contention is common. Allen _______________________________________________ Render mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/render
