Re: automake and DualCore

[Simon Richter]

Hi,

Thomas Porschberg schrieb:

> do Makefiles created from automake benefit from dualcore CPUs 
> and is the build process speeded up ?

Most Makefiles generated from automake are SMP safe and benefit from
multiple processors if make's -j option is used. They usually also
benefit from -j2 on single CPU systems already.

With DualCore systems, I'd assume the actual speedup towards a true
uniprecossor system to be minimal, as the actual compilation speed is
limited by the memory bandwidth, which still remains the same regardless
of how many cores are in the CPU.

> Are there any measurement data available ?

No. Compilation speed depends on quite a lot of variables; you may
experience speedups for projects with a lot of small C files and
slowdowns for projects with large C++ files, or vice versa.

> (Background is that I plan to buy a new PC and would like to know if it
> is worthwhile to consider such a system.)

DualCore is much like 64 bit. Noone needs it, everyone thinks it is
faster while it clearly is not, it costs more money and dissipates more
heat. I'd say go for a G4 or, if you need an Intel, Pentium M and enjoy
the silence[1].

   Simon

[1] also, a box that eats only 25W instead of 150W will save you 200
EUR/year