1

Here is the command I issued: 

root@vishal-Think:~# echo "0" > /proc/irq/0/smp_affinity

And here is the error:

-bash: echo: write error: Input/output error

The ls command shows that root has write permissions:

root@vishal-Think:~# ls -l /proc/irq/0/smp_affinity
-rw------- 1 root root 0 May 21 16:30 /proc/irq/0/smp_affinity

Please tell me how I could fix this.

Another question of mine is that even after disabling irqbalance and rebooting the machine, I still see interrupts going to cpus other than cpu0. Why could that be happening?

Improve this question

2 Answers 2

Reset to default
0

IRQ 0 is timer interrupt and is handled only by core 0. This can not be moved to other cores.

Improve this answer
-1

/proc is a virtual file system and although the information appears to be a file, you do not write to the files.

See http://www.tldp.org/LDP/Linux-Filesystem-Hierarchy/html/proc.html

I am not sure what the problem is with your hardware or how to fix it. Please update your question describing the problem and what you did to generate that error message.

Improve this answer
3
  • As shown in my post, I tried to echo into /proc/irq0/smp_affinity. Is that not the correct method? If not, then how do I change the interrupt affinity in Ubuntu.
    – user1274878
    May 22, 2014 at 14:16
  • That is a very broad question and I would refer you to the linux kerenl documentation. On this site, I suggest you identify your hardware and describe the problem. What makes you think you need to change the interrupt affinity?
    – Panther
    May 22, 2014 at 14:52
  • normally the echo as root should work temporarily. Obviously you have a problem, hard to know the best solution, may well be to file a bug report against the linux kernel.
    – Panther
    May 22, 2014 at 14:56

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .