Danny Braniss <[EMAIL PROTECTED]> writes:
> i've been doing some experiments with vinum, and doing a make buildworld
> (with obj on the same vinum)
> without soft-updates ~ 1 hour
> with soft-updates ~ 40 minutes
> which is a bit better than 3% :-)
>
> what i can't figure out is why -j 4 didn't make any difference.
Because your I/O system is already saturated. The point with -jNN is
that one job can run while another is waiting for I/O to complete and
vice versa, but as your CPU gets faster the time spent actually
compiling etc. becomes insignificant next to the time spent doing I/O,
and if you're already doing I/O as fast as you can there's no room for
improvement. On a machine with a slower CPU or a faster I/O system,
you'd see improvement.
DES
--
Dag-Erling Smorgrav - [EMAIL PROTECTED]
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