3.2.11. /proc/interrupts

3.2.11. /proc/interrupts

This file records the number of interrupts per IRQ on the x86 architecture. A standard /proc/interrupts looks similar to the following:

  0:   80448940          XT-PIC  timer   
  1:     174412          XT-PIC  keyboard   
  2:          0          XT-PIC  cascade   
  8:          1          XT-PIC  rtc  
 10:     410964          XT-PIC  eth0  
 12:      60330          XT-PIC  PS/2 Mouse  
 14:    1314121          XT-PIC  ide0  
 15:    5195422          XT-PIC  ide1 
NMI:          0  
ERR:          0

For a multi-processor machine, this file may look slightly different:

	   CPU0       CPU1          
  0: 1366814704          0          XT-PIC  timer   
  1:        128        340    IO-APIC-edge  keyboard   
  2:          0          0          XT-PIC  cascade   
  8:          0          1    IO-APIC-edge  rtc  
 12:       5323       5793    IO-APIC-edge  PS/2 Mouse  
 13:          1          0          XT-PIC  fpu  
 16:   11184294   15940594   IO-APIC-level  Intel EtherExpress Pro 10/100 Ethernet  
 20:    8450043   11120093   IO-APIC-level  megaraid  
 30:      10432      10722   IO-APIC-level  aic7xxx  
 31:         23         22   IO-APIC-level  aic7xxx 
NMI:          0 
ERR:          0

The first column refers to the IRQ number. Each CPU in the system has its own column and its own number of interrupts per IRQ. The next column reports the type of interrupt, and the last column contains the name of the device that is located at that IRQ.

Each of the types of interrupts seen in this file, which are architecture-specific, mean something different. For x86 machines, the following values are common:

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