Why a Direct, 500 Mbit Tailscale Link Only Gave Me 10 Mbit for One Stream

Mon, 08 Jun 2026 00:00:00 +0000

The Problem

My self-hosted Jellyfin was slow whenever I connected to it from abroad over Tailscale. My ISP upload is about 500 Mbit/s, but streams stuttered and iperf3 over the tunnel only managed ~10 Mbit/s:

$ iperf3 -c jellyfin-host
[  5]   0.00-10.00  sec  11.9 MBytes  10.0 Mbit/s

It wasn’t a relay or routing issue — tailscale status showed a direct connection (not a DERP relay):

$ tailscale status
100.xx.xx.xx   jellyfin-host   linux   active; direct xx.xx.xx.xx:41641

So: direct, low-latency, half a gigabit of upload available — and still only 10 Mbit/s for a single stream.

Jellyfin on LTe - Today I Learned

Why a Direct, 500 Mbit Tailscale Link Only Gave Me 10 Mbit for One Stream

The Problem