>> 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
