FreeBSD 8.0, HyperV and non-uniform processors.

[Chuck Swiger]

Hi--

On Jan 11, 2010, at 10:43 AM, Paul Halliday wrote:
> Is this warning as harmful as it sounds:
> 
> WARNING: Non-uniform processors.
> WARNING: Using suboptimal topology.
> 
> More info:
> 
> CPU: Intel(R) Xeon(R) CPU           E7330  @ 2.40GHz (2304.83-MHz 686-class CPU)
> ACPI APIC Table: <VRTUAL MICROSFT>
> FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
> FreeBSD/SMP: 0 package(s) x 4 core(s)
> cpu0 (BSP): APIC ID:  0
> cpu1 (AP): APIC ID:  1
> WARNING: Non-uniform processors.
> WARNING: Using suboptimal topology.
> 
> Unfortunately I am forced to use this setup. Is there anything I can
> do? Should I even be worried?

This comes from the SMP probing code in i386/i386/mp_machdep.c (and similar for amd64):

        if (mp_ncpus % (cpu_cores * cpu_logical) != 0) {
                printf("WARNING: Non-uniform processors.\n");
                printf("WARNING: Using suboptimal topology.\n");
                return (smp_topo_none());
        }

smp_topo_none() means that the system assumes none of the L1/L2 cache levels are shared; for a virtual machine, this is probably correct, so you should not be unduly concerned.

-- 
-Chuck