rmbt-client 1.1.1

RMBT network measurement client — performs ping, download, and upload speed tests against an RMBT measurement server

rmbt-client (Python)

RMBT network measurement client written in Python. Performs ping, download, and upload phases against an RMBT measurement server and submits results to the control server.

Requirements

• Python 3.7+
• No third-party dependencies (stdlib only: ssl, socket, threading, urllib)

Usage

python -m rmbt_client --host https://measure.example.com

Run with a specific thread count and duration:

python -m rmbt_client --host https://measure.example.com --threads 4 --duration 10

Skip TLS verification against a local test server:

python -m rmbt_client --host https://localhost:8080 --no-tls-verify

Options

Flag	Description
-h, --host URL	Control server base URL (required)
-p, --port PORT	Override test server port
-u, --uuid UUID	Client UUID (uses/creates ~/.rmbt_client_uuid if omitted)
-t, --threads N	Force thread count for download and upload (overrides pre-test)
-d, --duration SECS	Test duration in seconds (default: from control server)
--ws	Use WebSocket (RMBTws) framing instead of plain HTTP upgrade
--http	Use plain HTTP upgrade (RMBThttp) — overrides auto-detection
--no-tls-verify	Skip TLS certificate verification (insecure)
--debug	Print control server request/response JSON
--intermediate	Print upload throughput every 40 ms per thread
--help	Print help

Performance

Starting with v1.1.0 the download and upload hot loops run inside a small C extension (rmbt_loop) that calls Py_BEGIN_ALLOW_THREADS before entering the tight recv()/send() loop. This releases the GIL for the entire bulk-data phase, allowing all measurement threads to transfer data truly in parallel.

The extension is compiled automatically when the package is installed from source (requires gcc and python3-dev). Pre-built manylinux wheels are published to PyPI for the three architectures Home Assistant runs on:

Architecture	Covers
x86_64	NUC, generic x86 VM, Docker on x86
aarch64	Raspberry Pi 4 / 5, modern ARM boards (64-bit)
armv7l	Raspberry Pi 3 and older (32-bit)

When the extension is not available (e.g. unsupported platform, missing compiler) the client falls back silently to the pure-Python implementation.

Measured throughput

The numbers below are from a loopback test (127.0.0.1, 4 threads, 7 s) on an x86-64 machine. They reflect CPU throughput, not a real network:

Client	Download	Upload
Python 1.1.0 (C extension, loopback)	~94 Gbit/s	~68 Gbit/s
Python 1.0.0 (pure Python, loopback)	~8 Gbit/s	~6 Gbit/s
Rust (loopback)	~32 Gbit/s	~32 Gbit/s

No test on a real 100 Gbit/s network has been performed. On an actual high-speed link, factors such as NIC driver overhead, interrupt coalescing, and kernel socket buffer tuning will dominate long before the Python vs. C difference matters. For typical home and office connections (up to ~10 Gbit/s) either implementation is more than fast enough.

To force the pure-Python path for benchmarking or debugging:

RMBT_PURE_PYTHON=1 python -m rmbt_client --host https://measure.example.com

Protocol

1. POST /RMBTControlServer/settings → register client, receive UUID
2. POST /RMBTControlServer/testRequest → receive token, server address, thread count
3. Pre-test: 2-second single-thread GETCHUNKS download to determine chunk size and thread counts
4. Ping: 1 s / 10–100 pings
5. Download: multi-threaded GETTIME, all threads start simultaneously via threading.Barrier
6. Upload: multi-threaded PUTNORESULT
7. POST /RMBTControlServer/result

Supports both RMBThttp (plain HTTP upgrade) and RMBTws (WebSocket) variants.
TLS via the stdlib ssl module; control server HTTPS via urllib.request.