2.6.20-rc3
[root@squid ~]# rpm -q irqbalance
irqbalance-0.55-2.fc6
[root@squid ~]# uptime
 11:51:50 up 6 days, 30 min,  3 users,  load average: 5.31, 5.08, 4.02
[root@squid ~]# service irqbalance status
irqbalance (pid 2310) is running...
[root@squid ~]# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  0:  520209517          0          0          0   IO-APIC-edge      timer
  1:         12          0          0          0   IO-APIC-edge      i8042
  8:          1          0          0          0   IO-APIC-edge      rtc
  9:          0          0          0          0   IO-APIC-fasteoi   acpi
 12:        103          0          0          0   IO-APIC-edge      i8042
 14:          0          0          0          0   IO-APIC-edge      libata
 15:          0          0          0          0   IO-APIC-edge      libata
 20:     138736  188194096          0    6797630   IO-APIC-fasteoi   libata
 22:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb2, uhci_hcd:usb4
 23:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb1, uhci_hcd:usb3, ehci_hcd:usb5
2296:       1367          0          0  849270653   PCI-MSI-edge      eth1
2297:       1022  835083968          0          0   PCI-MSI-edge      eth0
NMI:      47756     146249      47617     146186
LOC:  516828752  517331906  516828611  517331771
ERR:          0
2.6.20-rc3-mm1
[root@squid kernel]# uptime
 12:17:54 up 1 day, 21:58,  2 users,  load average: 9.47, 9.79, 10.28
[root@squid kernel]# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  0:   60031592   61350247   22273772   21780215   IO-APIC-edge      timer
  1:          0          6          1          1   IO-APIC-edge      i8042
  8:          0          0          1          0   IO-APIC-edge      rtc
  9:          0          0          0          0   IO-APIC-fasteoi   acpi
 12:        148        283        104        136   IO-APIC-edge      i8042
 14:          0          0          0          0   IO-APIC-edge      libata
 15:          0          0          0          0   IO-APIC-edge      libata
 20:   10482795    1477821      93306     641628   IO-APIC-fasteoi   libata
 22:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb2, uhci_hcd:usb4
 23:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb1, uhci_hcd:usb3, ehci_hcd:usb5
2296:        427        426        436  134563009   PCI-MSI-edge      eth1
2297:        252        252  135926471        257   PCI-MSI-edge      eth0
NMI:          0          0          0          0
LOC:  164661140  165163503  164660992  165163305
ERR:          0