Minimising system compiling time

[Brian J. Tarricone]

I know this has already been answered, but I can't help poking fun...

Peter Humphrey wrote:

>I'm running Gentoo on a dual-Opteron box and from time to time I decide
>to recompile the entire system - absolutely everything on the disk apart
>from a handful of binary packages. Needless to say, this takes a long
>time, and I'd like to find the best setup for shortening it.
>  
>
Simple solution: stop wasting your time and don't recompile your 
system.  There's really no reason to do so, unless there's something 
broken about it and you're making a last-ditch effort to save it, or 
you've updated to a new gee-whiz compiler that supposedly can make your 
apps run faster (heavy skepticism here).  If you've decided to change 
your CFLAGS, you'll obviously need to do a system recompile to see a 
whole-system effect, but in most instances that just sounds like 
gentoo-itis.  I assume you bought a dual Opteron for more than just 
wasting CPU cycles compiling things over and over, no?

>I assume that using a standard virtual terminal, not running X but using
>the frame buffer, is the slowest because every scroll requires a redraw,
>and there must be many thousands of them, maybe millions once I've built
>a more complete system. So at the moment I'm using Terminal in XFce
>4.2.1, which doesn't suffer that limitation but X does still need to
>refresh the window a few times a second.
>  
>
As someone else mentioned, using 'screen' is probably the easiest way to 
do it, though IIRC you lose scrollback capability.  Redirecting output 
of 'emerge' to /dev/null (or to a file, if you care about the output) 
should help as well.  Contrary to your opinion, I'd also imagine that 
running the compile directly on a console (i.e., not in X) would work as 
well.  I can't be certain, but I seriously doubt the framebuffer driver 
actually writes to the framebuffer while you're on a different VC.  If 
you have a particularly large framebuffer, you'll be able to see more of 
the output if it fails (switching between consoles causes you to lose 
scrollback).

On a side note, this has exactly what to do with Xfce?  I would think 
#gentoo or forums.gentoo.org would be a more on-topic place for this.  
This list gets a good amount of traffic; let's try to keep it all 
on-topic if possible.

    -brian