Text console scrolling
From: Geert Uytterhoeven <hidden>
Date: 2007-07-18 15:10:39
Hi all, I was trying to find the optimal scrolling strategy for ps3fb just when many fbcon changes went in, and I want to share my findings with you. Below are the results for my text console scrolling benchmark (execution time in seconds of cat'ing a big text file) on the PS3, for various video modes, screen rotations (you can fit lots of debug output on a rotated 1920x1200 screen ;-), and font, using the default FBINFO_DEFAULT vs. FBINFO_DEFAULT | FBINFO_READS_FAST flags. 2.6.22-ga5fcaa21 is mainline from yesterday, 2.6.22-gcb32da04 is mainline from today: 2.6.22-ga5fcaa21 2.6.22-gcb32da04 mode rot font DEFAULT READS_FAST DEFAULT READS_FAST 480p 0 default8x16 7.32 6.63 7.49 5.18 480p 1 default8x16 11.39 5.79 11.60 7.60 480p 2 default8x16 7.35 4.34 7.50 3.90 480p 3 default8x16 11.39 8.85 11.61 9.31 720p 0 default8x16 13.04 15.91 13.33 9.28 720p 1 default8x16 22.76 12.73 23.17 18.35 720p 2 default8x16 13.10 10.22 13.34 7.30 720p 3 default8x16 22.60 19.65 23.03 19.56 1080p 0 default8x16 20.76 34.25 21.09 14.98 1080p 1 default8x16 35.13 23.82 35.78 26.27 1080p 2 default8x16 20.69 21.51 21.12 11.57 1080p 3 default8x16 34.98 37.03 35.68 29.23 WUXGA 0 default8x16 24.92 46.83 25.52 18.05 WUXGA 1 default8x16 41.19 31.08 41.98 28.61 WUXGA 2 default8x16 25.00 29.11 25.56 13.74 WUXGA 3 default8x16 41.20 49.49 42.02 34.79 480p 0 lat4-19 7.20 6.57 7.35 5.12 480p 1 lat4-19 11.19 6.02 11.36 7.86 480p 2 lat4-19 7.21 4.32 7.36 3.83 480p 3 lat4-19 11.12 8.90 11.33 9.08 720p 0 lat4-19 12.69 15.57 12.94 9.09 720p 1 lat4-19 22.43 12.92 22.86 17.46 720p 2 lat4-19 12.71 10.04 13.08 7.19 720p 3 lat4-19 22.50 20.02 22.89 20.21 1080p 0 lat4-19 20.31 33.99 20.75 14.87 1080p 1 lat4-19 34.60 24.06 35.26 25.19 1080p 2 lat4-19 20.39 21.37 20.79 11.51 1080p 3 lat4-19 34.50 37.45 35.24 29.13 WUXGA 0 lat4-19 24.72 46.92 25.26 18.06 WUXGA 1 lat4-19 40.98 32.32 41.77 30.52 WUXGA 2 lat4-19 24.80 29.13 25.28 13.73 WUXGA 3 lat4-19 41.25 50.26 42.25 35.50 Yesterday, FBINFO_READS_FAST was faster in some cases, but much slower in others, so I didn't really know whether I should enable it or not. Today, FBINFO_READS_FAST is faster in all test cases, so the choice is clear. Note that there are still a few cases where today's fastest option is a bit slower than yesterday's fastest option. With kind regards, Geert Uytterhoeven Software Architect Sony Network and Software Technology Center Europe The Corporate Village · Da Vincilaan 7-D1 · B-1935 Zaventem · Belgium Phone: +32 (0)2 700 8453 Fax: +32 (0)2 700 8622 E-mail: Geert.Uytterhoeven@sonycom.com Internet: http://www.sony-europe.com/ Sony Network and Software Technology Center Europe A division of Sony Service Centre (Europe) N.V. Registered office: Technologielaan 7 · B-1840 Londerzeel · Belgium VAT BE 0413.825.160 · RPR Brussels Fortis Bank Zaventem · Swift GEBABEBB08A · IBAN BE39001382358619