* Kevin Day <[EMAIL PROTECTED]> [000421 20:24] wrote:
>
> Has anyone attempted to create a double buffered version of cp(1)? When
> copying from one disk to another, disk activity seems to ping-pong between
> the two, rather than keeping both active at the same time.
>
> If I were to fork and do something similar to afio, or maybe even doing
> something weird like using sendfile(it's faster than it sounds, and
> zero-copy), does anyone think I'd see any kind of speed boost?
>
> I'm effectively getting a little less than half the performance of just
> writing files filled with zero's, so I'm guessing this is where the
> bottleneck is, correct?
extend (using truncate) and then mmap() the destination file, then
read() directly into the mmap()'d portion.
I'd like to see what numbers you get. :)
--
-Alfred Perlstein - [[EMAIL PROTECTED]|[EMAIL PROTECTED]]
"I have the heart of a child; I keep it in a jar on my desk."
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