pito-compare

A terminal: cat demo.toml shows a small TOML file with a title, a unit, higher is better, two parties and three rows; pcmp demo.toml –out charts prints charts/demo-paired.png and charts/demo-ratio.png; pcmp demo.toml –kind bars –out charts prints one PNG per party; file shows a 1080 px wide PNG.

pito-compare draws benchmark comparison charts as PNGs, part of PITO MD. You write the numbers in a small JSON or TOML file, and pcmp draws them as dark, crisp charts in a hand-drawn pixel font: two or more parties side by side on one axis, how many times faster or slower one is than another, or plain bars. A chart takes 13 to 23 ms from start to PNG on disk, 39 to 64 times faster than matplotlib drawing the same data.

Paired bars: parse speed of parser v2 against parser v1 in two groups, with 2.5× faster, same speed and 3.2× slower tags, a marked row and two notes

At a glance

	pcmp
Time per chart, start to PNG on disk	13.2 ms single bars, 14.6 ms balanced ratios, 22.6 ms paired bars
Against matplotlib 3.11, same data	39× to 64× faster (844 to 871 ms per chart)
Peak memory	13.3 MB (matplotlib: 82.5 MB)
Binary	1.2 MB (Linux x86_64, release profile, stripped)
Dependencies	5 direct: png, serde, serde_json, toml, and clap for the command line
Needs to run	nothing: one binary, no Python, no plotting library, no fonts on the system

Measured on 2026-10-14 on an AMD Ryzen 9 9950X (32 threads) under Linux while the machine was busy with other work; times are the median of 50 runs, a new process per chart. Measure it yourself.

What it is

Benchmark results read best as a picture, and a picture that looks the same every time. pito-compare is the chart drawer of pito-codecs’ benchmarks made into a tool, with its exact look: the colours, the 5x7 pixel font, 1080 px wide. There is no plotting library: the canvas, the font and the PNG writer are a few hundred lines of Rust, so a chart is drawn the same, pixel for pixel, on every machine.

It comes two ways: pcmp, the command line, and pito_compare, a Rust library that draws the same charts from data built in code.

Where to go next

Install pcmp and draw a first chart.
Compare two versions: paired bars and the balanced ratio chart.
Compare three or more: pick who the tags compare with, and charts where lower is better.
Draw single bars when there is nothing to compare.
Pick the colours of each party.
Show text or your own ratio in place of a value.
Read a refusal: what pcmp says when a data file is wrong.
Draw from Rust with the library.
Measure pcmp against matplotlib.
Reference: the command line, the data format, the API, the changelog.