From 113bbe17ab28c5617167b38a6f02b1273cede963 Mon Sep 17 00:00:00 2001
From: Laszlo Magyar <lmagyar1973@gmail.com>
Date: Thu, 9 May 2024 20:13:46 +0200
Subject: [PATCH] Linux optimizations for subnet routers and exit nodes

---
 tailscale/Dockerfile                                        | 1 +
 tailscale/rootfs/etc/s6-overlay/s6-rc.d/post-tailscaled/run | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/tailscale/Dockerfile b/tailscale/Dockerfile
index e82181dc..7a9aee07 100755
--- a/tailscale/Dockerfile
+++ b/tailscale/Dockerfile
@@ -10,6 +10,7 @@ ARG BUILD_ARCH=amd64
 ARG TAILSCALE_VERSION="v1.66.0"
 RUN \
     apk add --no-cache \
+        ethtool=6.6-r0 \
         ipcalc=1.0.3-r0 \
         iproute2=6.6.0-r0 \
         iptables=1.8.10-r3 \
diff --git a/tailscale/rootfs/etc/s6-overlay/s6-rc.d/post-tailscaled/run b/tailscale/rootfs/etc/s6-overlay/s6-rc.d/post-tailscaled/run
index acd3fb52..4e463fc8 100755
--- a/tailscale/rootfs/etc/s6-overlay/s6-rc.d/post-tailscaled/run
+++ b/tailscale/rootfs/etc/s6-overlay/s6-rc.d/post-tailscaled/run
@@ -12,6 +12,12 @@ declare login_server
 declare tags
 declare keyexpiry
 
+# Linux optimizations for subnet routers and exit nodes
+# Based on: https://tailscale.com/kb/1320/performance-best-practices#linux-optimizations-for-subnet-routers-and-exit-nodes
+# Note: Changes made via ethtool are not persistent and will be lost after the machine shuts down.
+# Note: Executing it before "tailscale up" to avoid warning messages
+ethtool -K $(ip route show 0/0 | cut -f5 -d' ') rx-udp-gro-forwarding on rx-gro-list off
+
 # Default options
 options+=(--hostname "$(bashio::info.hostname)")