Hi!
High software interrupt load with low traffic.
Top:
%Cpu(s): 0.1 us, 0.0 sy, 0.0 ni, 74.4 id, 0.1 wa, 0.0 hi, 25.4 si, 0.0 st
Router passes less than 1 Gbps. CPU Intel E31220 3.10GHz, network Intel 82599ES.
cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
0: 6 0 0 0 IO-APIC 2-edge timer
1: 0 8 0 0 IO-APIC 1-edge i8042
4: 0 19 0 0 IO-APIC 4-edge ttyS0
8: 0 0 1 0 IO-APIC 8-edge rtc0
9: 0 0 0 0 IO-APIC 9-fasteoi acpi
12: 9 0 0 0 IO-APIC 12-edge i8042
16: 0 0 66 0 IO-APIC 16-fasteoi ehci_hcd:usb1
18: 0 0 0 0 IO-APIC 18-fasteoi i801_smbus
23: 0 0 0 30 IO-APIC 23-fasteoi ehci_hcd:usb2
24: 0 0 0 41344 PCI-MSI 512000-edge ahci[0000:00:1f.2]
36: 932930925 0 1 0 PCI-MSI 1050624-edge eth2-TxRx-0
37: 0 860083798 0 1 PCI-MSI 1050625-edge eth2-TxRx-1
38: 1 0 856861005 0 PCI-MSI 1050626-edge eth2-TxRx-2
39: 0 1 0 845176337 PCI-MSI 1050627-edge eth2-TxRx-3
40: 0 0 11480 0 PCI-MSI 1050628-edge eth2
NMI: 0 0 0 0 Non-maskable interrupts
LOC: 6747264 8559704 6703691 7071717 Local timer interrupts
SPU: 0 0 0 0 Spurious interrupts
PMI: 0 0 0 0 Performance monitoring interrupts
IWI: 36 95 22 102 IRQ work interrupts
RTR: 2 0 0 0 APIC ICR read retries
RES: 2134540 1929130 1922021 1923403 Rescheduling interrupts
CAL: 1689 2126 1799 2110 Function call interrupts
TLB: 180 184 196 190 TLB shootdowns
TRM: 0 0 0 0 Thermal event interrupts
THR: 0 0 0 0 Threshold APIC interrupts
DFR: 0 0 0 0 Deferred Error APIC interrupts
MCE: 0 0 0 0 Machine check exceptions
MCP: 531 532 532 532 Machine check polls
HYP: 0 0 0 0 Hypervisor callback interrupts
HRE: 0 0 0 0 Hyper-V reenlightenment interrupts
HVS: 0 0 0 0 Hyper-V stimer0 interrupts
ERR: 0
MIS: 0
PIN: 0 0 0 0 Posted-interrupt notification event
NPI: 0 0 0 0 Nested posted-interrupt event
PIW: 0 0 0 0 Posted-interrupt wakeup event
How to find the cause of the problem?