Crate sim_fabric

Simulate a device comprising a rectangular fabric.

The model is constructed the specified fabric and traffic generators and sinks connected to all of the fabric ports.

The traffic generators can be configured to send different traffic patterns in order to evaluate the performance of the fabric.

Examples

Note: in all the following comments the assumption is that a default 1GHz clock is being used. If the default clock frequency were to be changed then these calculations would be invalid.

Running a basic all-to-all simulation

cargo run --bin sim-fabric --release -- --kib-to-send 1024 --stdout --traffic-pattern all-to-all-fixed

In order to achieve the maximum throughput it is essential to make the frame sizes a multiple of the port width. For example, with a 128-bit port and the 20-byte ethernet frame overhead an ideal frame size would be something like 1484:

cargo run --bin sim-fabric --release -- --port-bits-per-tick 128 --frame-overhead-bytes 20 --frame-payload-bytes 1484 --kib-to-send 1024 --stdout

This achieves the peak bandwith at one port of 14.9 GiB/s and if run with a balanced communcation pattern it can achieve that at each port (357.6 GiB/s for the default 24-port fabric):

Note: A throughput of 342.70 GiB/s or less may be observed because the src/dest pairing is random and a source will not send to itself. Try a different value for --seed to observe this behaviour.

cargo run --bin sim-fabric --release -- --port-bits-per-tick 128 --frame-overhead-bytes 20 --frame-payload-bytes 1484 --kib-to-send 1024 --traffic-pattern all-to-all-fixed --seed 3 --stdout

Modules

frame_gen

source_sink_builder

Library functions to build parts of the sim-fabric application.