From: Stefan Bruda <bruda@cs...> - 2007-01-29 20:57:41
I keep seeing the boot arguments "noapic acpi=force irqpoll
pci=routeirq" floating around), however in my case "noapic" disables
one processor. I get in the logs:
SMP: Allowing 2 CPUs, 0 hotplug CPUs
PERCPU: Allocating 32384 bytes of per cpu data
Built 1 zonelists. Total pages: 512208
Kernel command line: auto BOOT_IMAGE=linux ro root=803 resume2=file:/dev/sda3:0x6e52c0
noapic acpi=force irqpoll pci=routeirq
Misrouted IRQ fixup and polling support enabled
This may significantly impact system performance
then CPU#0 comes up, then I get:
SMP alternatives: switching to UP code
ACPI: Core revision 20060707
ACPI: setting ELCR to 0200 (from 0c00)
SMP motherboard not detected.
Using local APIC timer interrupts.
Detected 10.390 MHz APIC timer.
testing NMI watchdog ... OK.
Brought up 1 CPUs
By contrast, without the "noapic" option The "SMP disabled" part gets
SMP alternatives: switching to SMP code
Booting processor 1/2 APIC 0x1
and then CPU#1 comes up too.
How come that you guys are using "noapic" then? What am I missing? I
am running a 64-bit installation; my kernel config can be seen at
If it was so, it might be; and if it were so, it would be; but as
it isn't, it ain't. That's logic.
--Lewis Carroll, Through the Looking-Glass
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