Benchmarks

Benchmarks

This page records compile time, run time and peak memory for every example. The same scene, size and frame count run in three.js. A standalone probe compares Mojo 1.1 to Mojo 1.0.

The numbers come from one machine. Other machines differ. The refresh command is in How to measure examples.

Machine

• Date: 2026-09-19
• OS: Darwin 25.6.0
• CPU: arm
• Mojo 1.1: Mojo 1.1.0 (8189361e)
• Mojo 1.0: not installed
• Node: v24.20.0
• three.js backend: cpu-flat
• A Mojo program that does nothing: 0.014 s
• A Node process that does nothing: 0.027 s

What the columns measure

Column	Meaning
compile	mojo build, in seconds. Paired in the 1.0 table.
run	The built binary or the Node process, whole, in seconds
three.js frames only	The draw loop alone, timed inside the Node process
RSS	Peak resident set of that run, in MiB

Paired columns sit next to each other. Dark green is faster by 30% or more. Light green is faster by 10% to 30%. Yellow is within 10%. A cell with no color is the slower side, or a value with no pair.

The two run columns do not measure the same work. ThreeMojo transforms, clips, lights, textures and composites every frame in linear light on the CPU. It encodes every frame into an APNG and writes the file. three.js draws with WebGL when the gl package loads. three.js has no CPU renderer of its own.

When gl does not load, the cpu-flat backend fills the same projected triangles with each material's flat color and a depth test. It does no lighting, no textures, no sRGB and no transparency, and it writes no file. Most of a cpu-flat run is Node starting and importing three.js. The baselines under Machine say what each process costs before it draws anything.

Read the three.js frames only column against the ThreeMojo run column minus the Mojo baseline. That is the nearest the page comes to like against like.

The pin is Mojo 1.1. The 1.0 column is the same source built by Mojo 1.0.0. The probe is a standalone triangle fill that imports nothing from ThreeMojo.

Example vs three.js

Example	Size	Frames	ThreeMojo compile (s)	ThreeMojo run (s)	three.js run (s)	three.js frames only (s)	ThreeMojo RSS (MiB)	three.js RSS (MiB)
triangle	320×240	1	0.392	0.018	0.040	0.002	14.3	64.0
spin	160×120	24	0.397	0.020	0.039	0.002	20.0	64.1
cube	240×180	36	0.580	0.027	0.043	0.006	44.6	65.4
cubes	260×200	48	1.112	0.040	0.047	0.010	59.1	65.5
uv	320×200	2	1.021	0.020	0.040	0.002	16.0	64.1
textured	260×200	36	1.109	0.038	0.044	0.006	44.1	64.8
glass	260×200	36	1.127	0.035	0.045	0.009	51.8	65.5
floor	320×200	30	1.106	0.050	0.045	0.008	41.2	64.6
photo	260×200	36	1.240	0.041	0.042	0.007	44.1	65.1
lamps	260×200	36	1.112	0.036	0.052	0.013	44.1	65.6
first_scene	320×240	1	1.087	0.023	0.040	0.002	16.3	63.9
lit_scene	320×240	36	1.107	0.050	0.045	0.008	69.5	64.9
rotations	240×180	36	1.108	0.030	0.042	0.006	45.7	65.3
ortho	240×180	36	1.111	0.030	0.041	0.004	39.3	64.9
geometry	240×180	36	1.117	0.037	0.070	0.031	47.9	65.8
instances	240×180	36	1.113	0.032	0.047	0.011	46.2	65.4
raycast	240×180	36	1.165	0.038	0.058	0.018	47.8	66.1
curves	240×180	36	1.150	0.035	0.050	0.010	45.8	66.0
keyframes	240×180	36	1.202	0.030	0.044	0.006	45.8	65.2
skinning	240×180	36	1.127	0.035	0.041	0.004	45.9	65.5
phong	240×180	36	1.115	0.038	0.054	0.017	42.2	65.7
fog	240×180	36	1.115	0.029	0.042	0.006	45.8	65.5
culling	240×180	36	1.114	0.033	0.046	0.011	45.7	65.3
clipping	240×180	36	1.119	0.032	0.043	0.006	45.7	65.4
gpu_backend	240×180	36	1.166	0.032	0.049	0.012	45.8	65.4
exposure	240×180	36	1.117	0.043	0.042	0.006	42.0	65.2
model	240×180	36	1.211	0.032	0.043	0.006	45.8	65.3
orbit	240×180	36	1.108	0.033	0.043	0.006	47.8	65.7
clock	240×180	36	1.129	0.031	0.043	0.006	45.8	65.2
chain	240×180	36	1.123	0.031	0.042	0.006	46.1	65.2
additive	240×180	36	1.116	0.037	0.043	0.006	42.1	65.2
normals	240×180	36	1.122	0.039	0.053	0.015	42.2	65.5
fragments	240×180	36	1.131	0.037	0.047	0.009	45.7	65.3
edges	240×180	48	0.418	0.029	0.041	0.004	50.7	64.9

three.js backend for this run: cpu-flat. The gl package did not load, so three.js did not render. The cpu-flat backend fills the same triangles with each material's flat color and a depth test. It does no lighting, no textures, no sRGB and no transparency, and it writes no file. The three.js frames only column is that fill, timed inside the process. The rest of the three.js run column is Node starting and importing three.js.

Mojo 1.1 against Mojo 1.0

Program	1.1 compile (s)	1.0 compile (s)	1.1 run (s)	1.0 run (s)	1.1 RSS (MiB)	1.0 RSS (MiB)
probe	0.294	not installed	0.027	—	14.1	—
triangle	0.392	not installed	0.018	—	14.3	—
spin	0.397	not installed	0.020	—	20.0	—
cube	0.580	not installed	0.027	—	44.6	—
cubes	1.112	not installed	0.040	—	59.1	—
uv	1.021	not installed	0.020	—	16.0	—
textured	1.109	not installed	0.038	—	44.1	—
glass	1.127	not installed	0.035	—	51.8	—
floor	1.106	not installed	0.050	—	41.2	—
photo	1.240	not installed	0.041	—	44.1	—
lamps	1.112	not installed	0.036	—	44.1	—
first_scene	1.087	not installed	0.023	—	16.3	—
lit_scene	1.107	not installed	0.050	—	69.5	—
rotations	1.108	not installed	0.030	—	45.7	—
ortho	1.111	not installed	0.030	—	39.3	—
geometry	1.117	not installed	0.037	—	47.9	—
instances	1.113	not installed	0.032	—	46.2	—
raycast	1.165	not installed	0.038	—	47.8	—
curves	1.150	not installed	0.035	—	45.8	—
keyframes	1.202	not installed	0.030	—	45.8	—
skinning	1.127	not installed	0.035	—	45.9	—
phong	1.115	not installed	0.038	—	42.2	—
fog	1.115	not installed	0.029	—	45.8	—
culling	1.114	not installed	0.033	—	45.7	—
clipping	1.119	not installed	0.032	—	45.7	—
gpu_backend	1.166	not installed	0.032	—	45.8	—
exposure	1.117	not installed	0.043	—	42.0	—
model	1.211	not installed	0.032	—	45.8	—
orbit	1.108	not installed	0.033	—	47.8	—
clock	1.129	not installed	0.031	—	45.8	—
chain	1.123	not installed	0.031	—	46.1	—
additive	1.116	not installed	0.037	—	42.1	—
normals	1.122	not installed	0.039	—	42.2	—
fragments	1.131	not installed	0.037	—	45.7	—
edges	0.418	not installed	0.029	—	50.7	—

Mojo 1.0.0 compiles the probe, triangle, spin, cube and edges. It refuses the other examples.

PMREM and the coverage run

The heaviest suites now write a quarter to a half of the coverage records they wrote before issue #157. Every image is the same to the bit.

A coverage run writes one record for each statement that runs. So the cost of a suite under coverage follows the statements in its innermost loops, not its run time. test_pmrem takes a fifth of a second without coverage, but it wrote 14 GB under coverage. See Coverage tool.

Suite, every CPU module instrumented	Before	After
test_pmrem	13.95 GB, 390 s	3.63 GB, 99 s
test_renderer	3.22 GB, 84 s	2.35 GB, 70 s
test_environment	2.34 GB, 63 s	1.24 GB, 38 s
test_rasterizer	0.65 GB, 16 s	0.49 GB, 15 s

The times come from a Linux container with four shared cores, so they are approximate. The sizes are exact.

The changes:

• The PMREM blur finds its weights, sines, cosines and copy position once per pass. CubeUvCopy holds the position, and cube_uv_coordinate uses it too.
• A bilinear read wraps each of its two columns and two rows once.
• FloatColor and the CLAMP case of wrap_index have no statements to probe. Vector3.cross and the shadow texel clamp are one statement each.
• Spherical harmonics find only the weight they use.
• test_pmrem blurs four environments, not seven. Three tests only need a valid layout, and now use one made by hand.

Without coverage, a 256-texel cube prefilters in about 210 ms, from about 270 ms before.

The sums keep their order, so each blur gives the same bits. The Mojo compiler fuses a multiply and an add into one instruction when it can. Thus moving a product out of a loop can change the last bit. The blur keeps the cross product per tap for that reason. A scratch program compared the images before and after, bit for bit, at face sizes 16 to 256 and from a panorama.

Other benches

Program	Shows
bench/raster_bench.mojo	CPU against GPU rasterization across image sizes.
bench/scene_bench.mojo	Each stage of the CPU renderer, timed on its own, one worker and every core.
bench/probe.mojo	The 1.1 half of the compiler comparison.
bench/noop.mojo	A program that does nothing: the Mojo baseline.
bench/mojo10/probe.mojo	The 1.0 half. make lint excludes this file.