Linux list all IROs currently in use

Q. How do I list all IRQs currently used under CentOS Linux?

A.. There is a file called /proc/interrupts. The proc filesystem is a pseudo filesystem which is used as an interface to kernel data structures. It is commonly mounted at /proc.

This is used to record the number of interrupts per each IRQ on (at least) the i386 architecture. Very easy to read formatting, done in ASCII.

Display /proc/interrupts

Use cat or less command:
$ cat /proc/interrupts
Output:

           CPU0       CPU1       CPU2       CPU3       
  0:        187          0          0          0   IO-APIC-edge      timer
  1:      39922          0          0          0   IO-APIC-edge      i8042
  7:          0          0          0          0   IO-APIC-edge      parport0
  8:          4          0          0          0   IO-APIC-edge      rtc
  9:          1          0          0          0   IO-APIC-fasteoi   acpi
 12:     846774          0          0          0   IO-APIC-edge      i8042
 14:     105048          0          0          0   IO-APIC-edge      libata
 15:          0          0          0          0   IO-APIC-edge      libata
 16:    1069722          0          0          0   IO-APIC-fasteoi   libata, uhci_hcd:usb4, nvidia
 17:     105382          0          0          0   IO-APIC-fasteoi   eth0
 18:      83040          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb2, libata
 19:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb1, ehci_hcd:usb5
 20:     474168          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb3, ohci1394, ra0
 21:      10117          0          0          0   IO-APIC-fasteoi   bttv0
 22:     594327          0          0          0   IO-APIC-fasteoi   HDA Intel
NMI:          0          0          0          0 
LOC:    1754492    1545836    2085855    1878596 
ERR:          0
MIS:          0

🐧 Get the latest tutorials on Linux, Open Source & DevOps via RSS feed or Weekly email newsletter.

🐧 1 comment so far... add one


CategoryList of Unix and Linux commands
Disk space analyzersdf duf ncdu pydf
File Managementcat cp mkdir tree
FirewallAlpine Awall CentOS 8 OpenSUSE RHEL 8 Ubuntu 16.04 Ubuntu 18.04 Ubuntu 20.04
Modern utilitiesbat exa
Network UtilitiesNetHogs dig host ip nmap
OpenVPNCentOS 7 CentOS 8 Debian 10 Debian 8/9 Ubuntu 18.04 Ubuntu 20.04
Package Managerapk apt
Processes Managementbg chroot cron disown fg glances gtop jobs killall kill pidof pstree pwdx time vtop
Searchingag grep whereis which
User Informationgroups id lastcomm last lid/libuser-lid logname members users whoami who w
WireGuard VPNAlpine CentOS 8 Debian 10 Firewall Ubuntu 20.04
1 comment… add one
  • Adrian Oct 30, 2013 @ 11:04

    So let’s say I have a lot of interrupt:

    42: 30051 3989 1852 1164 6372 5528 3165 3893 PCI-MSI-edge eth0
    43: 324118 50177 57614 64707 209869 272543 119056 166394 PCI-MSI-edge ahci
    44: 21893 856 334 192 4661 14208 577 10006 PCI-MSI-edge ahci
    45: 11 1 1 0 0 0 1 1 PCI-MSI-edge mei_me
    46: 104 11 20 67 211 154 33 79 PCI-MSI-edge snd_hda_intel
    NMI: 2475 7594 343 5417 80 80 50 67 Non-maskable interrupts
    LOC: 811797 1437385 562591 1186174 67483 79097 53366 64000 Local timer interrupts
    SPU: 0 0 0 0 0 0 0 0 Spurious interrupts
    PMI: 2475 7594 343 5417 80 80 50 67 Performance monitoring interrupts
    IWI: 49091 42482 67738 54517 7948 8963 8777 10430 IRQ work interrupts
    RTR: 7 0 0 0 0 0 0 0 APIC ICR read retries
    RES: 421549 398075 408406 404770 220092 151531 204254 232130 Rescheduling interrupts

    How can I see what’s causing those, in order to find the source of the problem ?

Leave a Reply

Your email address will not be published.

Use HTML <pre>...</pre> for code samples. Still have questions? Post it on our forum