The crucial difference when comparing Apple's MP machines and the BeBox is the 603 is fundamentally lacking support at the CPU hardware level to enable the cache coherency you need to enable true SMP. The BeBox gets around this by playing some really ugly games with software and its performance goes completely in the toilet if you ever try to switch a thread between the two cores.Be probably used the same sort of weird hackery that Apple did with their MP machines except they got proper SMP working.
Nonetheless it did at one point work on at least an experimental level; I've already posted one reference, here's another. I imagine they pulled support for those machines from later kernels because of some combination of them being "idiosyncratic" in terms of implementation compared to later machines (Linux is known to have trouble with pre-Pentium Pro SMP machines even though technically 486 and Pentium MP boards exist that comply with the Intel MP standard as documented) and the fact that there simply aren't enough of them in circulation to make the effort worthwhile. In particular I'm betting that it turned out to be really difficult to implement the new scheduler that came with the 2.6 kernel release on those old machines, assuming Apple didn't support I/O routing like Intel does with their APIC/MP hardware. (IE, the Beige hardware might be easy enough to make work with a "Big Lock" sort of SMP but is harder to make play nice with more sophisticated algorithms.)No available Linux distro has proper, stable support for SMP on multiprocessor beige Macs; pretty much all of them don't even recognize the other processor.
Where there dual-CPU ANSes? I honestly can't remember. I'm googling it and it looks like no?The ANS is of course a completely different beast and I have no experience with any of them; A/UX and/or Linux may work fine in an SMP configuration on those but I can't say. Regardless, they're not Macs since they never ran the Mac OS.
Where there dual-CPU ANSes? I honestly can't remember. I'm googling it and it looks like no?
In any case, almost all the chipset hardware in an ANS matches that of a Power Macintosh 9500. The two major differences are the ANS has a modified memory controller to support parity memory, and it uses a Cirrus Logic VGA chip instead of the standard Apple framebuffer ASIC. (I'm guessing the latter was to leverage an existing driver in AIX, some low-end CHIRP RS/6000 hardware used the same.) It's mostly a ROM block (and the weird video) that prevents MacOS from running on them.
Doh, I forgot about that. My faulty memory filled in that it had the same framebuffer as the 7/8xx's stashed on the board, but thinking about it at all I know that's wrong.The 9500 did not have built in video.
Dual Processor Configuration:
In the 9600/200MP model, two PowerPC 604e microprocessors are on the processor card.
With applications that support the new multiprocessor API, the MP configuration
provides up to 2 times the performance of the equivalent single-processor computers.
The operation of the dual-processor configuration is asymmetric multiprocessing. One
processor is the primary processor: it runs the Mac OS and handles interrupts from the
I/O systems. The second processor runs MP tasks as set up by the primary processor.
256 MB RAM (+ 2x 8 or something that was causing issues)