Plex86 runs fine on my dual PPro with both processors enabled. I am running
2.2.13 kernel (I tried a 2.2.14, but it won't boot......period--so I don't
know if plex86 would run on it with SMP enabled or not).
So the problem is with whatever changes were made to the more recent kernels
(not that I have the brains to find or fix them, however.
As for plex86/SMP compatibility: what happens is similar to what happens on
WinNt if you run something not SMP-compatible--it only uses one CPU. It is
that simple. The LINUX default scheduler (in 2.2.13 anyway) seems to
respect this. Otherwise I have no idea what is going on (maybe the
scheduler in 2.4.x doesn't respect programs that don't know about more than
one CPU but operate directly on the hardware--like plex86).
Just my 2¢
Drew Northup, N1XIM
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf
> Of Ramon van Handel
> Sent: Friday, January 26, 2001 5:35 AM
> To: [EMAIL PROTECTED]
> Subject: Re: [plex86] NT port
>
>
> >> I thought that were built in to the processor package? - hence
> the local
> >> APIC support thing???
> >Ahh. There are apparently two different things: an IO-APIC,
> which is on some
> >CPUs, and an APIC, which is on some motherboards. All SMP
> machines have an
> >APIC, but an IO-APIC is optional per CPU, and not required for SMP.
>
> Uhh, no. It works like this:
>
> ,------ hardware ------. ,------ chip on motherboard ------. ,-
> processor -.
> perhiperal interrupt <---> IO/APIC <--(interrupt cpu map)-->
> LAPIC <---> CPU1
> <--(interrupt cpu map)-->
> LAPIC <---> CPU2
>
> The I/O APIC is programmed to deliver interrupts to specific CPUs. The
> LAPIC units on the CPUs pick the interrupt off the APIC bus.
>
> The I/O APIC exists only on SMP boxes, but all processors come
> with a LAPIC.
> For uniprocessors the LAPIC is not so interesting, but it does provide a
> few extra high-resolution timers that can be used (that wouldn't kill plex
> though).
> I can't imagine that this is related to the bug in the NT port.
>
> However, plex is not currently SMP-compatible, I believe.
>
> -- Ramon
>
>
>
>
