Minimum CPU to bridge 10G traffic?

I’m looking to bridge 10G Ethernet traffic between a Broadcom 10GBase-T NIC and an Intel SFP+ NIC. How much CPU would this require? Could it be done with something as old as an i3-2100?

Note, I’m not interested in any higher-level features, just L2 bridging. Thanks!

Why do you want to use a router to bridge?

Because I need to extend a layer 2 broadcast domain, and VyOS can do that for free with hardware I already have? Not sure I understand your question. I’m already doing this elsewhere, but in a VM with a much more powerful CPU.

I was just thinking it may be a better network design using a switch doing L2 bridging at 10 G speed. Probably more than two interfaces could be convenient also :wink:

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Oh sure, I could get a switch. But this is a home-based small business, so every penny matters, and like I said I’ve already got the NICs on hand. I also only need two client ports (one SFP and one RJ45) and one RJ45 uplink port. I can get a SFF PC with two PCIe x16 slots for as little as $65; the cheapest possible switch is the D-link at $200, and it only has two 10G RJ45 ports.

The only question is whether the i3-3240 in that $65 SFF PC is enough to forward traffic at anything close to line speed. I went ahead and bought it, because the seller has a decent return policy, so I guess I’ll find out!

Hello, @deafen!
It is really hard to predict such things, as this very depends on traffic type, network equipment and even configuration of a motherboard.
That’s why the answer can be got only after real tests. If you do them, please share results with us. This will be interesting.

You will always lose performance switching in software vs ASIC, but I’ve hit 8-9 Gbps with 2 cores on an e5-2670. The VyOS was a VM and the iperf hosts used for testing were both physically connected to the vmware host running the VyOS. I bet you will see great performance with that chip.

For comparison, your chip is over 200 passmark points ahead of mine on a single thread.
https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i3-3240+%40+3.40GHz&id=765
https://www.cpubenchmark.net/cpu.php?cpu=intel+xeon+e5-2670+%40+2.60ghz