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General IPv6 Topics => IPv6 on Linux & BSD & Mac => Topic started by: tjeske on July 08, 2021, 06:05:12 AM

Title: Multithreading/multicore support?
Post by: tjeske on July 08, 2021, 06:05:12 AM
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?
Title: Re: Multithreading/multicore support?
Post by: snarked on July 08, 2021, 08:45:29 AM
Is your OS kernel multi-core supporting?  Maybe the board routes all interruptes to core zero in hardware and that canít be changed.  Just things to check out.
Title: Re: Multithreading/multicore support?
Post by: tjeske on July 09, 2021, 08:26:40 PM
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?
Title: Re: Multithreading/multicore support?
Post by: snarked on July 10, 2021, 10:02:48 AM
I would not make that assumption.  Unless you compile your own kernel, SMP versions are not the default unless specifically stated.
Title: Re: Multithreading/multicore support?
Post by: tjeske on July 12, 2021, 08:13:33 AM
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.