On Mon, May 25, 2009 at 10:47 PM, Thomas Gleixner <tg...@linutronix.de> wrote:

Thank you for notice of 2.6.29.r-rt16 release.

This is a report about "/proc/interrupts" result in my development system.

* System requirements : Core2 Quad Q6600 , LV-676 Motherboard , SATA 160G, DDR2 3G , ftp://ftp.commell.com.tw/COMMELL/support/LV-676/BIOS/676x161.zip.

In summary, I can't get irq loadbalancing(/proc/interrupts) in my system using 2.6.29.4-rt16 linux kernel because of LV-676 motherboard's H/W problem. ( I disabled [ ]irqbalance - userspace with "ntsysv" command in this experiment . )

[geunsik@centos5.3 ~]$ [geunsik@centos5.3 ~]$ [geunsik@centos5.3 ~]$ cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 0: 136 0 0 0 IO-APIC-edge timer 1: 2 0 0 0 IO-APIC-edge i8042 3: 2 0 0 0 IO-APIC-edge 4: 2 0 0 0 IO-APIC-edge 6: 2 0 0 0 IO-APIC-edge floppy 7: 0 0 0 0 IO-APIC-edge lpptest 8: 1 0 0 0 IO-APIC-edge rtc 9: 1 0 0 0 IO-APIC-fasteoi acpi 16: 0 0 0 0 IO-APIC-fasteoi uhci_hcd:usb3 18: 15030 2133 4521 0 IO-APIC-fasteoi libata, libata, uhci_hcd:usb6 19: 1133 0 0 0 IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb7 20: 3 0 0 0 IO-APIC-fasteoi ehci_hcd:usb2, uhci_hcd:usb5 21: 0 0 0 0 IO-APIC-fasteoi uhci_hcd:usb4 223: 871 0 0 0 PCI-MSI-edge eth1 NMI: 0 0 0 0 Non-maskable interrupts LOC: 158448 161871 160140 161074 Local timer interrupts RES: 735 822 1378 1028 Rescheduling interrupts CAL: 3397 3408 1948 2452 function call interrupts TLB: 240 288 266 310 TLB shootdowns TRM: 0 0 0 0 Thermal event interrupts SPU: 0 0 0 0 Spurious interrupts ERR: 0 MIS: 0 [geunsik@centos5.3 ~]$

So, I asked Commell company about this problems. For reference, Belows is answer from their technical service team.

-- [ From te...@commell.com.tw] --------------------------------------------- Hi Sorry for keep you waiting. We had setn LV-676 motherboard to BIOS vendor for solution, still now no resond yet, any respond will pass to you.

We had constantly push for solution, and BIOS vendor is working on this issue and attempt to solve this problem, any message from them will let you know. BR K.H. Ooi

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Currently, I am using "smp_affinity" in this LV-676 mother board like belows.

Binary Hex CPU 0 0001 1 CPU 1 0010 2 CPU 2 0100 4 CPU 3 1000 8

[geunsik@centos5.3 ~]$ [geunsik@centos5.3 ~]$ echo 8 > /proc/irq/18/smp_affinity [geunsik@centos5.3 ~]$ for i in `ls -1 /proc/irq/*/smp_affinity`; do echo "smp affinity CPU3 +++ $i"; echo 8 > $i; done <-- assign irq to CPU3 [geunsik@centos5.3 ~]$ cat /proc/interrupts <---check irq-balancing

* Don't use irq affinity about timer irq [geunsik@centos5.3 ~]$ echo 8 > /proc/irq/0/smp_affinity -bash: echo: write error: Input/output error