cabletest/docs/README.md

cabletest docs

Project knowledge that moves and versions with the repo.

cabletest finds Ethernet cables that misbehave under sustained full-duplex 10 Gbit load. It exchanges raw Ethernet frames (no IP, no ARP) across a variety of sizes and payloads between two directly-cabled ports on one host, and attributes every problem it can to the cable rather than the host. It runs as PID 1 on a dedicated appliance with a framebuffer UI; development happens on the same machine under Arch. The target of measurement is the cable, not throughput — line rate is a means to stress the physical layer.

General:

• state.md — where things are now: the box and what's in it, the bench driver, every-boot steps. All current-placement state lives here and only here.
• hardware.md — host rules: interface conventions, tuning, how to run.
• measurement.md — how to measure correctly; performance results and dead ends.
• xdp.md — the AF_XDP datapath experiment: what it proved, what rebuilding it needs, why it can't run on the X520.

Per-device (each directory: device doc + its datasheets):

• nics/ — the transport rule, the comparison table, and one directory per NIC: x520, connectx-5, x710, e810.
• modules/ — module inventory, media-lies table, the shared IEEE register set, RollBall protocol, cable-length physics, and one directory per module: fs, wiitek, fibergaga.