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Re: About Multiprocessing




Hello,

this is interesting, why is this this way? Nobody contributed SMP support yet, or does real SMP support hurts real-time functionality? Or is this just "historic relict"?

Thanks,
Karel

On Tue, 20 Dec 2005, Jiri Gaisler wrote:


We are currently developing an MP system with four LEON3 (SPARC) cpus in a shared memory configuration. We are using the MP extensions and memory-based communication, works fine so far. Pitty that RTEMS doesn't have support for SMP, i.e. one image with multiple threads executed by multiple cpus. eCos has this and it scales well up to ~ four processors. With RTEMS, we must have a separate image for each cpu, which wastes memory and complicates linking and program loading.

Jiri.

Ralf Corsepius wrote:
On Tue, 2005-12-20 at 20:11 +1100, Angelo Fraietta wrote:

there are over 40 CPUs (or rather BSPs) that RTEMS SUPPORTS

... but only 3 of these BSPs claim to support multiprocessing: m68k/mvme147s, m68k/mvme136, powerpc/psim :)

i.e. multiprocessing for all cpus but the m68k and powerpc, probably has
never been tested at all ;)

Ralf


.



-- Karel Gardas kgardas@objectsecurity.com ObjectSecurity Ltd. http://www.objectsecurity.com