Re: timer interrupt handled by CPU0 only

Alexander Clouter
2009-05-13T14:08:48Z

qmh524 <qmh524@gmail.com> wrote:
>
> I have start irqbalance service. Why the timer interrupt only happend in CPU0
>
irqBALANCE...you could also ask why all your eth0 IRQ's are on CPU3 or
your ATA action is on CPU2.

It's my understanding you *steer* IRQ's to a CPU, you do not round-robin
them across all the CPU's.

Cheers

> $ sudo service irqbalance status
> irqbalance (pid 2390) is running...
> $ cat /proc/interrupts
> CPU0 CPU1 CPU2 CPU3
> 0: 21487296 0 0 0 IO-APIC-edge timer
> 1: 3 0 0 0 IO-APIC-edge i8042
> 8: 1 0 0 0 IO-APIC-edge rtc
> 9: 0 0 0 0 IO-APIC-level acpi
> 12: 4 0 0 0 IO-APIC-edge i8042
> 74: 18 0 0 0 IO-APIC-level
> uhci_hcd:usb1, uhci_hcd:usb3, ehci_hcd:usb4
> 82: 0 0 0 0 IO-APIC-level uhci_hcd:usb2
> 90: 1934 0 45886283 0 IO-APIC-level libata
> 98: 0 0 0 0 IO-APIC-level libata
> 106: 120 0 0 22824923 PCI-MSI eth0
> 169: 16933 0 9370507 0 IO-APIC-level ioc0
> NMI: 43241 26776 33934 29946
> LOC: 21487192 21487118 21487046 21486887
> ERR: 0
> MIS: 0

--
Alexander Clouter
.sigmonster says: A hammer sometimes misses its mark - a bouquet never.