On 30 Jan 2009, Michel Dänzer stated: >Trying current xf86-video-ati Git might be good, but my main suggestion >would be to try xserver Git server-1.6-branch with EXA.
OK. Do I need to upgrade Mesa or anything related at the same time? (I'm currently on libdrm 2.4.1, Mesa a few commits past 7.2.0). >> Both Konsole 3.5.9 (without a background pixmap) and a recent xterm are >> equally sluggish; > > xterm uses core fonts by default, did you configure it differently? I just used -fa/-fs to force client-side fonts. >> X: fbFetch_a1 10.92 >> dixLookupPrivate 7.04 >> fbStore_a1 3.70 >> mmxCombineAddU 3.06 >> pixman_image_composite 2.58 > > [...] > >> So it looks like we *are* doing huge numbers of fetches from VRAM, >> judging by the massive time spent in calls upon pixman's fbFetch(). > > No, at least with EXA, fb*_a1 can't access video RAM directly, as the > EXA core currently never migrates pixmaps of bpp < 8 to video RAM. This was a profile with XAA, not EXA. Here's a more comprehensive set of results (using xterm at all times, 'non-AA' forced by using my preferred terminal font, the bitmap font Neep Alt), started and stopped by hand so it's all quite crude, roughly 60s per benchmark run (so I can't explain sysprof's saying that some runs spent 90s in X: on a single core that seems quite unlikely): XAA, 16, AA: fbCompositeSolidMask_nx8888x0565Cmmx 59.25 (time in X, 90.12) XAA, 24, AA: fbCompositeSolidMask_nx8888x8888Cmmx 57.12 (time in X, 85.03) EXA, 16, AA: dixLookupPrivate 23.17 visually much faster than XAA, occasionally degrades to XAA speed EXA, 24, AA: dixLookupPrivate 26.83 XAA, 16, non-AA: fbFetch_a1 12.43 %time in X, 79.96) XAA, 24, non-AA: fbFetch_a1 14.51 (time in X, 87.60) (v. slow in konsole, very slightly faster-seeming in xterm but profile results identical so this is just an artifact of differing repaint strategies) EXA, 16, non-AA: fbFetch_r5g6b5 53.40, fbFetch_a1 5.75 (time in X, 95.88) horrendously, impossibly slow, >10s for a single screen repaint EXA, 24, non-AA: fbFetch_a1 12.40 (89.34s in X) much better than the abominable depth 16 results, back to XAA speed XAA, 16, core: cat, bash, xterm; CPU load nearly nil; screen a blur far too fast to read highest consumer in X, at <1s, DrawTETextScanlineWidth7() XAA, 24, core: cat, bash, xterm; CPU load nearly nil; screen a blur far too fast to read; highest consumer in X, at <1s, DrawTETextScanlineWidth7() EXA, 16, core: pixman_fill_mmx 22.17, fbGlyph16 15.83, CPU still pegged by X, in sharp contrast to non-EXA; (time in X, 62.58) EXA, 24, core: pixman_fill_mmx 37.51, fbGlyph32 13.63 (time in X, 69.48) better than anything else bar core XAA In general, core fonts much faster than client-side fonts, 24-bit as fast or faster than 16-bit (this has changed in the about eight years since I paid any attention to it last, and DRI no longer stops working in 24-bit mode: maybe I'll switch), XAA faster than EXA with the single exception of anti-aliased fonts, which I don't use in terminals and text editors because I like my text small enough that antialiasing is uglier than not. I must say, looking at these crude benchmark results I'm wondering if this client-side font thing wasn't an appealing diversion. Yes, they're pretty, and more flexible than core fonts: but all of a sudden simply simply redrawing the screen has become so CPU-intensive that a screen scroller can peg the CPU without any real effort :( isn't X supposed to use *less* CPU time than the apps that call on it? :((( > To avoid a1 pictures, you could try using anti-aliasing everywhere, i.e. > don't choose any bitmap fonts and don't disable anti-aliasing for small > font sizes. The benchmarks show that this would indeed speed things up. It would also eliminate every font I use day-to-day and give me piercing headaches. No thanks, let's find another way. :) >> (++) RADEON(0): Depth 16, (--) framebuffer bpp 16 >> (II) RADEON(0): Pixel depth = 16 bits stored in 2 bytes (16 bpp >> pixmaps) > > Is it any better in depth 24, or even worse? (See above.) Better under EXA: sometimes better, sometimes worse under XAA (better for antialiased fonts only, all others worse, or too fast to tell in the case of core fonts). _______________________________________________ xorg mailing list xorg@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/xorg