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SubjectReading from /dev/fb0 very slow?
Hi!

I did some benchmarks, and my framebuffer is *way* faster when writing
than when reading:

root@bug:/home/pavel# time cat /tmp/test > /dev/fb0
0.01user 0.08system 0.09 (0m0.097s) elapsed 93.13%CPU
root@bug:/home/pavel# time cat /dev/fb0 > /dev/null
0.00user 0.62system 0.62 (0m0.620s) elapsed 99.93%CPU
root@bug:/home/pavel#

That is 6 times slower! This is also very visible in X, where moving
regions is expensive, while just drawing regions is fast. For example
gnome-terminal is *way* faster *with* transparent background option.

Any idea why such assymetry? [This is toshiba 4030cdt with vesafb and
2.4.5]

Pavel
--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org
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