Benchmarks

This benchmark compares the throughput of a Remoc channel with serializing and writing the same records directly over TCP.

Benchmark setup

A sender pushes records as fast as it can for five seconds and a receiver reads them. The same transfer runs twice: once over an rch::mpsc channel, and once over a plain TCP connection that serializes the same records with the same codec and frames them itself. The plain TCP implementation provides the reference for each Remoc result.

The record
#[derive(Clone, Serialize, Deserialize)]
struct Sample {
    id: u64,
    timestamp: u64,
    source: String,
    valid: bool,
    value: f64,
}
One message
// A message is a batch of records.
let batch = vec![Sample::new(); records_per_message];

// Sent over rch::mpsc, or serialized
// into the socket by hand.
tx.send(batch).await?;

With Postbag, one record encodes to 64 bytes, so a batch of 1024 records is a 64 KiB message. Parallel transfer is configured with with_parallel(4), allowing several messages to be encoded and decoded concurrently to keep up with high-bandwidth links.

Bandwidth and round-trip time are emulated in the process, so a slow or distant connection can be measured without one.
Link Bandwidth Round-trip time
LAN 125 MB/s 0 ms
Wi-Fi 12 MB/s 10 ms
LTE 6 MB/s 50 ms
WAN 25 MB/s 100 ms

Results generated with Remoc 0.20.0 compiled with Rust 1.97.1, on a 13th Gen Intel Core i9-13900K running Linux 7.1.

Records per second

Throughput depends on the number of records batched into each message. Each panel represents one emulated link and compares Remoc with the plain TCP implementation using the same serialization.

Records per second against records per message, for a Remoc channel and a plain TCP reference, one panel per link.
From four records per message, the Remoc rch::mpsc channel and plain TCP results converge. In these tests, the configured LTE and WAN round-trip delays do not reduce throughput.

Throughput relative to plain TCP

The results are shown as a share of the raw TCP throughput available on each link, represented by the dotted line. The grey bars include serialization and framing; the pink bars additionally include Remoc's multiplexing, chunking and flow control.

Throughput as a share of a raw TCP transfer, for a Remoc channel and a plain TCP reference, one panel per link.
From 16 records per message on, a channel and the plain connection both reach what the link allows on LAN, Wi-Fi and LTE, at 98–100% of a raw transfer.

Reproduce the results

The benchmark suite is part of the Remoc repository. It tests each configured layer, codec and link, prints the results per link, and writes a JSON report from which plot.py generates the charts. 

$ cd bench/perf
$ cargo run --release -- --out results.json
$ ./plot.py results.json

Benchmark suite on GitHub →