I am terminating my tunnel with OpenWrt running on a cheapish router, ARM-based (MediaTek).
I've found that I get quite poor performance of only 300 Mbps max from my 1 Gbps legacy connection. If I run htop I see that only one core is getting all the load (though it shows 4 cores, while the specs actually say it's just dual core?).
So I was wondering if the sit/6in4 kernel module maybe doesn't support multithreading? Does anybody know more about it?
Is your OS kernel multi-core supporting? Maybe the board routes all interruptes to core zero in hardware and that can't be changed. Just things to check out.
I would assume that the OpenWrt linux kernel is multi-core supporting. But maybe the support of the SoC is not fully multi-core supporting? But I think other operations work with multi-threading on this unit. How would I check out this interrupt thing?
I would not make that assumption. Unless you compile your own kernel, SMP versions are not the default unless specifically stated.
Hmhmhm, seems like network traffic is one IRQ and that can't be distributed over several cores. So, you can have one core for routing, and the other cores are left for other tasks. But information seems very limited.