I installed kernel 2.6.18-194.3.1 and configuration at smp_affinity file to fffffff. but still only one core is in use.
i can control moving from one core to another but cant activate both cores parallel.

I've looked around, but I can find nothing that matches my problem exactly on the web.

root@alonf ~]# uname -a
linux alonf 2.6.18-194.3.1.el5PAE #1 SMP Sun May 2 04:42:25 EDT 2010 i686 i686 i
86 GNU/Linux

If you can move one application from one core to the other, I am sur both cores are in use. Maybe your application is single-threaded? Try to start more than one application and look what happens.

i am trying to configure eth0 for example to fffffff ... and only the cpu0 is in use ... when i configuring it to 00000002 - only cpu 1 is in use ... they never works together.


[root@alonf ~]# cat /proc/interrupts
CPU0 CPU1
0: 8154879 33295 IO-APIC-edge timer
1: 3 0 IO-APIC-edge i8042
7: 0 0 IO-APIC-edge parport0
8: 3 0 IO-APIC-edge rtc
9: 0 0 IO-APIC-level acpi
12: 4 0 IO-APIC-edge i8042
14: 60070 0 IO-APIC-edge ide0
15: 72718 0 IO-APIC-edge ide1
50: 0 0 IO-APIC-level ata_piix
58: 112 0 PCI-MSI HDA Intel
66: 124207 0 PCI-MSI eth0
169: 5049 112 IO-APIC-level uhci_hcd:usb3, i915@pci:0000:00
209: 3 0 IO-APIC-level ehci_hcd:usb1
217: 0 0 IO-APIC-level ehci_hcd:usb2, uhci_hcd:usb5
225: 0 0 IO-APIC-level uhci_hcd:usb4, uhci_hcd:usb6
233: 0 0 IO-APIC-level uhci_hcd:usb7
NMI: 0 0
LOC: 8193392 8248279
ERR: 0
MIS: 0

I don't understand what you want to do. Why are you trying to attach a network device to a cpu-core? Just run a bunch of applications and have a look at htop, and you will se if both cores a active.