Also seeing 2 x quad-core system slower that 2 x dual core
kometen at gmail.com
Fri Nov 30 07:21:16 PST 2007
> > Yes, if the claim is that the hardware is absolutely identical apart
> > from one having two quad-core CPUs instead of two dual-core, the next
> > step is to disable half of the CPUs and confirm that the problem goes away.
> Just comming back to this today, will do a side by side compare of the dmesg
> later to make sure that they *are* identical as claimed, but the idea of
> disabling half the CPU's is an excellent one!
> Aha, brilliant idea!
> > Check dmesg for the APIC numbers corresponding to the CPUs you want to
> > disable and add the corresponding entries to /boot/loader.conf, e.g.:
> You mean this bit?
> FreeBSD/SMP: Multiprocessor System Detected: 8 CPUs
> cpu0 (BSP): APIC ID: 0
> cpu1 (AP): APIC ID: 1
> cpu2 (AP): APIC ID: 2
> cpu3 (AP): APIC ID: 3
> cpu4 (AP): APIC ID: 4
> cpu5 (AP): APIC ID: 5
> cpu6 (AP): APIC ID: 6
> cpu7 (AP): APIC ID: 7
For completeness sake :-) you could try to disable the second
quad-core-cpu completely rather than 2 cores on each unit and redo the
When lenity and cruelty play for a kingdom,
the gentlest gamester is the soonest winner.
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