[bpi-r2] network interrupts

Hi,

I made some testing with streaming and see while routing between lan and wan/pppoe interrupts counting up only on cpu0. It stops from time to time.i have not much cpu usage in top,but it seems that interrupts causing this

Afair there was a way ro change cpu or maybe use all cpus…but don’t remember how. Afaik it was called affinity,but found only the crypto driver thread

$ cat /proc/interrupts | grep eth
240:  147961822          0          0          0  MT_SYSIRQ 199 Level     1b100000.ethernet
241:  136396797          0          0          0  MT_SYSIRQ 198 Level     1b100000.ethernet

so only first cpu is used…some more interrupts operating only on cpu0. i found no dropping or similar on networking interfaces i use for this (eth0, lan0 and wan), vlan and pppoe had no statictics in ethtool

i tried moving irq to different CPU (counting not clear)

echo 2 > /proc/irq/240/smp_affinity #2 moves to cpu1
echo 4 > /proc/irq/241/smp_affinity #4 moves to cpu2

[14:22] root@bpi-r2-e:~ (349)# cat /proc/interrupts | grep eth
240:  147967496       1210          0          0  MT_SYSIRQ 199 Level     1b100000.ethernet
241:  136403870          0        728          0  MT_SYSIRQ 198 Level     1b100000.ethernet

after ~1 minute i see these (~1000 interupts /min)…isn’t this much??

i guess the interrupts are caused by NAT…my structure is wan + vlan + pppoe with NAT => routed to lan0 through iptables (which may also cause CPU-load/interrupts)