mikkeli
cbb2aba8b0
Consuming JSON means the familiar iperf3 text layout has to be rebuilt, so a pure formatter turns each event back into a line — binary units for transfer totals, decimal units for bitrates, matching how iperf3 quotes each. The view model keeps the interval series and the end summary as data alongside the transcript, and a stat row shows current/total, mean, peak and sample count off that series. A chart can be driven from the same list without re-parsing text. Repaints are coalesced on a 250ms timer rather than one per event. Reports can now arrive several times a second across many streams, and each rebuild re-renders the whole transcript, so notifying per event made the cost of drawing scale with the report rate — which competes with the test itself for CPU and skews the measurement. Warm-up intervals (-O) are marked omitted by iperf3 and are kept out of the series so they cannot drag the mean down. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
iperf3-gui
A Flutter-based Android GUI wrapper for iperf3, the popular network performance measurement tool.
Features
- Client-mode network throughput testing
- Configurable server, port, duration and parallel streams
- Live iperf3 output, streamed line by line while the test runs
- Stop a running test early
- Copy the transcript to the clipboard
- iperf3 3.19 compiled into the app as a native library — no external binary
Architecture
lib/
├── domain/
│ ├── models/ # TestConfiguration, Iperf3Result
├── data/
│ └── services/ # Iperf3Service (MethodChannel → JNI)
├── ui/
│ └── features/
│ └── test_run/ # TestRunScreen, TestRunViewModel
└── main.dart # App entry point
android/app/src/main/
├── kotlin/…/IperfRunner.kt # MethodChannel handler, runs tests off the platform thread
└── cpp/iperf_jni.c # JNI bridge into the iperf3 API
See docs/README.md for the data flow, the native API surface and the design decisions behind them.
Why JNI instead of executing a binary
Android SELinux in Enforcing mode blocks execve() from the untrusted_app
domain, so shipping an iperf3 ELF in assets and running it via Process.start()
fails with "Permission denied". iperf3 is therefore compiled as a shared library
(libiperf3jni.so) and called in-process over JNI.
assets/iperf3/ still holds the pre-compiled binaries from that earlier
approach. They are not declared in pubspec.yaml, so they are not packaged into
the APK, and nothing in the app reads them.
Building
Prerequisites:
- Flutter 3.47+
- Android SDK with platform android-36
- JDK 17
- NDK r28+ and CMake 3.22.1 (for the native build)
flutter pub get
flutter analyze
flutter test
flutter build apk --debug
adb install -r build/app/outputs/flutter-apk/app-debug.apk
Testing against a local server
iperf3 -s -p 5201 # on a machine on the same network
ip -4 addr show # note its address
Enter that address in the app, then press GO.
Dependencies
- Dart:
provider - Native: iperf3 3.19 + cJSON, built by CMake for
armeabi-v7aandarm64-v8a
License
MIT — bundled iperf3 3.19 is BSD-3-Clause licensed.