The /proc/interrupts timer entry is dangling a little. With PREEMPT_RT the entry doesn't get updated .. My system after two hours uptime, CPU0 CPU1 0: 56 0 IO-APIC-edge timer 1: 2 0 IO-APIC-edge i8042 4: 1450 0 IO-APIC-edge serial 6: 3 0 IO-APIC-edge floppy 8: 0 0 IO-APIC-edge rtc 9: 0 0 IO-APIC-fasteoi acpi 12: 4 0 IO-APIC-edge i8042 14: 824890 0 IO-APIC-edge ide0 17: 182 0 IO-APIC-fasteoi HDA Intel 20: 0 0 IO-APIC-fasteoi uhci_hcd:usb2 21: 0 0 IO-APIC-fasteoi libata, ehci_hcd:usb1, uhci_hcd:usb4 22: 0 0 IO-APIC-fasteoi uhci_hcd:usb3 23: 7515 0 IO-APIC-fasteoi uhci_hcd:usb5, eth0 NMI: 0 0 LOC: 1749635 1749614 ERR: 0 Daniel - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html