Vous vous êtes toujours demandé pourquoi il y avait une interruption "cascade" et un canal dma "cascade".
Si vous ne le saviez pas, essayez les 2 commandes suivantes, et étudiez de près les 2 schémas electroniques ci-après.
stephane@debian:~$ cat /proc/interrupts
CPU0
0: 1564385 XT-PIC timer
1: 4578 XT-PIC i8042
2: 0 XT-PIC cascade
5: 667 XT-PIC ALI 5451
8: 4 XT-PIC rtc
9: 68760 XT-PIC acpi
10: 1 XT-PIC ohci_hcd:usb1, radeon@pci:0000:01:05.0
11: 18194 XT-PIC yenta, eth0
12: 147740 XT-PIC i8042
14: 30423 XT-PIC ide0
15: 54490 XT-PIC ide1
NMI: 0
LOC: 0
ERR: 0
MIS: 0
stephane@debian:~$ cat /proc/dma
4: cascade
Phénomène de cascade des interruptions
Phénomène de cascade des DMAs
Processeurs plus récents
stephane@ubuntu:~$ cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
0: 26 1 0 0 IO-APIC-edge timer
1: 1 0 0 1 IO-APIC-edge i8042
8: 0 0 1 0 IO-APIC-edge rtc0
9: 0 0 0 0 IO-APIC-fasteoi acpi
12: 0 2 0 2 IO-APIC-edge i8042
16: 212 208 199 204 IO-APIC-fasteoi uhci_hcd:usb3, uhci_hcd:usb8, radeon@pci:0000:04:00.0
17: 147 133 137 151 IO-APIC-fasteoi HDA Intel
18: 0 1 1 1 IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb7
19: 0 0 0 0 IO-APIC-fasteoi uhci_hcd:usb6
20: 0 1 1 1 IO-APIC-fasteoi ohci1394
21: 2474 2482 2508 2452 IO-APIC-fasteoi uhci_hcd:usb4
22: 875 864 855 809 IO-APIC-fasteoi HDA Intel
23: 10122 10103 10117 10132 IO-APIC-fasteoi ehci_hcd:usb2, uhci_hcd:usb5
27: 6662 6706 6693 6724 PCI-MSI-edge ahci
28: 1568 1562 1551 1587 PCI-MSI-edge eth0
NMI: 0 0 0 0 Non-maskable interrupts
LOC: 60182 69223 58123 34623 Local timer interrupts
SPU: 0 0 0 0 Spurious interrupts
CNT: 0 0 0 0 Performance counter interrupts
PND: 0 0 0 0 Performance pending work
RES: 68 107 75 76 Rescheduling interrupts
CAL: 111 102 112 137 Function call interrupts
TLB: 1064 1187 980 1304 TLB shootdowns
TRM: 0 0 0 0 Thermal event interrupts
THR: 0 0 0 0 Threshold APIC interrupts
MCE: 0 0 0 0 Machine check exceptions
MCP: 3 3 3 3 Machine check polls
ERR: 0
MIS: 0
stephane@ubuntu:~$ cat /proc/dma
4: cascade