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SubjectRe: Reading from /dev/fb0 very slow?
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> I did some benchmarks, and my framebuffer is *way* faster when writing
> than when reading:

That is quite normal.

> 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]

Writes to a PCI device can be queued or posted. Reads from a PCI device for
obvious reasons have to stall the CPU until the data returns.

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