Performance, memory and CPU usage tests of Tailscale, Netbird, Zerotier and Wireguard (+ UPD)
Made a quick test of mesh VPN clients. Test was performed between host and a VM, both running Kubuntu 23.04. VM ran on KVM with a virtio network adapter.
Test machine is oldish laptop with an i5-2540M, so VPN performance was probably CPU bound. Still, tests help to understand how different mesh VPNs compare against each other.
Tailscale surprisingly was the fastest, even faster than plain Wireguard, despite being userspace. But it also consumed more memory (245 MB after the iperf3 test!) and CPU.
Netbird's CPU usage is so low I almost doubt if that's fair comparison, most usage might be by kernel, since it uses kernel Wireguard. I don't know how to measure that better. Memory usage is moderate. For some reason it wasn't as fast as plain Wireguard.
Zerotier has the lowest memory usage, but is the slowest. Although this would probably only matter on LAN. Hope upcoming v2 closes the gap.
This time I've measured total system memory usage to account for kernel usage. No surprises here, just a bit more data. Tailscale confirmed to consume a lot more memory under load.
How I've measured memory and CPU usage:
All commands and measurements are done in the VM, the only thing on host is VM itself and iperf3 client
Boot the VM, start iperf3 server, all mesh VPN services are disabled beforehand
Then, for every service:
Run sar -r ALL 2 5 to determine the baseline, note the average kbavail (it accounts for the fact that not all caches are actually reclaimable, see man)
Start the service
Run sar -r ALL 2 5, note the average kbavail, difference with the baseline goes to the "Pre / post start, Δ mem avail" row
Run iperf3 client on the host: iperf3 -c *IP* -t 90 or iperf3 -c *IP* -t 90 --bidir
During the test, run sar -u ALL -r ALL 5 10 , note the average kbavail and CPU idle %
After all tests are done, average of all kbavail during tests goes to the "Pre / during iperf3 tests, avg Δ mem avail" row; and 100% minus average of all CPU idle % during tests goes to the "CPU usage during iperf3 tests" row
Stop the service
Run sync; sudo sysctl -q vm.drop_caches=3
Here's raw data, so you can recalculate using anything else instead of kbavail
I've minimized number of running apps on the host that could affect performance (looking at you, Firefox). This resulted in some overall performance increase, and both Netbird and Wireguard performed almost identically to Tailscale in iperf3, overperforming Zerotier by ~2.4 times (the same ratio as in my initial test).
I've also added bidirectional iperf3 test, so that both ends transmit and receive data. That didn't significantly affect the performance, except for Tailscale. Tailscale performance halved in this test.
Nice test! I’m a Tailscale user and I liked it being faster than others. I don’t care about memory usage but curious why there is a big gap 🤔 Like its using 20x more memory than Zerotier.
Tailscale is written in Go with lots of dependencies. It also has a lot more features, to the point some would call that too much 😅 Zerotier is pretty lean and in C. That would explain those 55 MB idle memory usage difference. But those 245 MB after iperf3 test though... I can't explain, but it's consistent and repeatable.
Is it possible the others are using the Wireguard kernel module? In that case, a lot of the memory usage will be in kernel/system memory, and just looking at the app's memory usage won't be the full story.
Netbird uses kernel Wireguard module, right. Is there a way to measure kernel memory / CPU usage attributed to Wireguard?
Zerotier, which has the lowest memory usage, does not use Wireguard at all, they have their own custom protocol and it's userspace AFAIK.