LAN Speed Test

A tiny tool for testing how fast your WiFi/Ethernet is, You need two devices for that. Alternatively, you can either put speedtestd on a server somewhere, or tunnel it through ngrok or similar, for an actual internet speed test. Note that this is not production grade or anything like that, I'm building this as I learn Rust.

Building

You can build for your current platform, and also build an Android binary for use in Termux, for example.

Building for your current platform is easy, just run SKIP_ANDROID_BUILD=1 ./build.sh or cargo build --release.

In order to build for Android, you need to have the Android NDK set up, enable the aarch64-android-linux target in rustup (assuming your Android device is 64bit, all recent ones should be. But if it isn't, the target triple you need to enable will be different, and you'll need to modify build.sh). You must set ANDROID_NDK to the path to the install side-by-side NDK (usually something like $ANDROID_HOME/ndk/[VERSION]) and HOST_ARCH to the host architecture (e.g. darwin-x86_64 on MacOS, run ls $ANDROID_NDK/toolchains/llvm/prebuilt to check yours). For example:

you@YourPC:~ ANDROID_NDK=$ANDROID_HOME/ndk/[VERSION] HOST_ARCH=darwin-x86_64 SKIP_PLATFORM_BUILD=1 ./build.sh

Running

There are two binaries built: lan-speed-test and speedtestd.

• speedtestd is the server and runs on the provided port (default 30000) and exposes a /stream endpoint that streams /dev/zero to the client. (e.g. speedtestd 42069).
• lan-speed-test is the client, which connects to the server and measures fast the data comes in. You can invoke it with either an IP:PORT combo (e.g. lan-speed-test 127.0.0.1:42069), or a URL (which may or may not have the /stream path, e.g. lan-speed-test https://my-server-url.some-provider.cloud), or nothing it all, in which case, it'll try to find a running speedtestd instance on the available network interfaces and connect to the first one it encounters.
  • N/B: The auto discovery process uses MDNS, which should work fine on Windows(?) and MacOS, but you might need to set up Avahi on Linux.

TODO

• Have lan-speed-test automatically try and find a running speedtestd on the available network interfaces, if one isn't provided. Implemented using mdns_sd.
• Make this work on Windows, by generating the data to stream to the client somehow. Implemented a Stream for this, so it should work now. Haven't actually tried building on Windows, though.
• A timeout for the server discovery process
• A time limit for the speed test
• A mobile app (Flutter / React Native?)

Troubleshooting

• If you're having clang complain that it can't find -lgcc, follow the steps here: rust-lang/rust#85806 (comment) (You likely only have to do it for the particular arch you're targeting.)