[G4] dual processors

[Perry The Cynic]

--On September 8, 2005 9:27:15 PM -0500 Bob Schmidt <bob58523 at charter.net> 
wrote:

> Hi All,
>
> I have a real dumb question. I have an old AS4000 alpha server with 2
> 400mhz 64bit processors. On this computer only one processor is  working,
> the other is a kind of stand by. On a G4 500mhz with dual  processors are
> both working together or is one just on stand by.

Macintoshes running Mac OS X use "symmetric multiprocessing." Both 
processors have "equal rights;" there is no "master" and "standby" 
processor.

Of course, if your Mac doesn't do much right now, the system will slow down 
one processor to save energy (and heat). And if you only run one program 
and that program isn't multi-threaded (written to use multiple processors), 
then you will see one processor work for that program and the other taking 
care of the rest of the system (background activity, graphics, etc.)

Note that all this was *not* true in Mac OS 9, where the second processor 
can only be used for a very limited set of activities.

Cheers
  -- perry
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Perry The Cynic                                             perry at cynic.org
To a blind optimist, an optimistic realist must seem like an Accursed Cynic.
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