I couldn't find any answer about this by googling.
Here my output of /proc/interrupts:
pi@raspberrypi:~ $ cat /proc/interrupts
CPU0
17: 3380 ARMCTRL-level 1 Edge 2000b880.mailbox
18: 36 ARMCTRL-level 2 Edge VCHIQ doorbell
27: 120102 ARMCTRL-level 35 Edge timer
40: 0 ARMCTRL-level 48 Edge bcm2708_fb DMA
42: 9594 ARMCTRL-level 50 Edge DMA IRQ
44: 0 ARMCTRL-level 52 Edge DMA IRQ
45: 0 ARMCTRL-level 53 Edge DMA IRQ
53: 0 ARMCTRL-level 61 Edge 20215080.spi
56: 3568399 ARMCTRL-level 64 Edge dwc_otg, dwc_otg_pcd, dwc_otg_hcd:usb1
77: 3648 ARMCTRL-level 85 Edge 20804000.i2c
78: 0 ARMCTRL-level 86 Edge 20204000.spi
80: 3800 ARMCTRL-level 88 Edge mmc0
81: 4 ARMCTRL-level 89 Edge uart-pl011
FIQ: usb_fiq
Err: 0
My question is: what is the meaning of the numbers on the 4th column? (1, 2, 35, 48...).
Some information about my system.
pi@raspberrypi:~ $ uname -a
Linux raspberrypi 4.19.66+ #1253 Thu Aug 15 11:37:30 BST 2019 armv6l GNU/Linux
pi@raspberrypi:~ $ cat /proc/cpuinfo
processor : 0
model name : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 697.95
Features : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7
Hardware : BCM2835
Revision : 0013
Serial : 00000000be0130ff