>    Using -pipe is a big win. On a system with not enough RAM, and not using
>    -pip, the stuff gets written to intermidiate files. If this is an MFS /tmp
>    then this is swap, else it is ordinary file system. On a system with less
>    memory and -pipe the processes get swapped. If the swapper/pager is good
>    enough then what is the difference ?
> 
> Even if you scheduled optimally for this situation, you'd still have
> to switch your working set 2*((N/PIPE_BUF)-1) times more, where N is
> the amount of data output between stages.  And if you come up with
> an optimal scheduler, I'd love to see it...

OK - So I fogot there were more than two stages :)

Regards,
-- 
Peter Galbavy                                           peter@wonderland.org
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in Wonderland                              http://www.wonderland.org/~peter/
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