x11perf

Joel McCormack at DEC's Western Research Lab wrote it in the late 1980s, with contributions from Phil Karlton among others. It runs hundreds of tiny tests — dots, lines, ten-pixel rectangles, text, CopyArea, window creation — and reports operations per second for each. The companion script x11perfcomp lines up several runs in one table, so you can see exactly which operation a new driver made slower.

Workstation vendors wanted a single number for the brochure, so a weighted average called the Xmark was distilled from the results. It proved about as meaningful as such numbers usually do: servers got tuned for the measured operations rather than for the programs people actually ran. As a driver debugging tool, x11perf is still in use.