Go ECS Benchmarks

Comparative benchmarks for Go Entity Component System (ECS) implementations.

Disclaimer: This repository is maintained by the author of Ark.

Benchmark candidates

ECS	Tested	Latest	Activity
Ark	v0.8.3
Donburi	v1.15.7
go‑gameengine‑ecs	v0.9.0
GOKe	v1.2.6
unitoftime/ecs	v0.0.3
Volt	v1.7.0

Candidates are always displayed in alphabetical order.

In case you develop or use a Go ECS that is not in the list and that want to see here, please open an issue or make a pull request. See the section on Contributing for details.

In case you are a developer or user of an implementation included here, feel free to check the benchmarked code for any possible improvements. Open an issue if you want a version update.

Features

ECS	Type-safe API	ID-based API	Relations	Events[1]	Batches[2]	Command buffer
Ark	✅	✅	✅	✅	✅	❌
Donburi	✅	❌	❌	❌	❌	❌
go‑gameengine‑ecs	❌	✅	❌	❌	❌	❌
GOKe	✅	❌	❌	❌	❌	✅
unitoftime/ecs	✅	❌	❌	❌	❌	✅
Volt	✅	❌	❌	✅	❌	❌

[1] ECS lifecycle events, allowing to react to entity creation, component addition, ...
[2] Faster batch operations for entity creation etc.

Benchmarks

Last run: Mon, 01 Jun 2026 11:47:54 UTC
CPU: Intel(R) Xeon(R) Platinum 8370C CPU @ 2.80GHz

For each benchmark, the left plot panel and the table show the time spent per entity, while the right panel shows the total time.

Note that the Y axis has logarithmic scale in all plots. So doubled bar or line height is not doubled time!

All components used in the benchmarks have two float64 fields. The initial capacity of the world is set to 1024 where this is supported.

Query

N entities with components Position and Velocity. 10x N entities with components Position.

• Query all [Position, Velocity] entities, and add the velocity vector to the position vector.

N	Ark	Ark (tables)	Donburi	ggecs	GOKe	uot	Volt
1	64.57ns	70.10ns	63.39ns	48.17ns	7.34ns	18.27ns	79.12ns
4	17.87ns	18.49ns	29.63ns	15.55ns	2.82ns	6.88ns	20.57ns
16	5.74ns	5.35ns	22.17ns	7.40ns	1.47ns	4.58ns	6.10ns
64	2.67ns	2.00ns	19.29ns	5.72ns	0.84ns	3.46ns	2.48ns
256	1.95ns	1.05ns	19.92ns	5.19ns	0.70ns	3.22ns	1.60ns
1k	1.82ns	0.90ns	19.92ns	5.06ns	0.68ns	3.27ns	1.37ns
16k	1.78ns	0.84ns	21.12ns	5.05ns	0.81ns	3.26ns	1.28ns
256k	1.77ns	0.83ns	22.89ns	5.09ns	0.80ns	3.20ns	1.26ns
1M	1.84ns	0.96ns	30.63ns	5.05ns	1.07ns	3.20ns	1.35ns

Note: Donburi, GOKe, unitoftime/ecs, and Volt use a callback-based approach for their query loops. As a result, iteration speed may degrade if the callback contains complex logic and the Go compiler is unable to inline it.

Query fragmented, inner

Query where the matching entities are fragmented over 32 archetypes.

N entities with components Position and Velocity. Each of these N entities has some combination of components C1, C2, ..., C5, so entities are fragmented over up to 32 archetypes.

• Query all [Position, Velocity] entities, and add the velocity vector to the position vector.

N	Ark	Ark (tables)	Donburi	GOKe	ggecs	uot	Volt
1	65.25ns	71.57ns	62.71ns	7.40ns	45.74ns	17.19ns	83.12ns
4	32.42ns	39.13ns	32.91ns	5.11ns	19.04ns	14.89ns	67.25ns
16	23.18ns	31.76ns	26.46ns	4.51ns	12.45ns	24.54ns	62.06ns
64	13.08ns	16.25ns	23.17ns	3.43ns	8.51ns	14.55ns	32.74ns
256	4.92ns	4.80ns	21.20ns	2.68ns	5.76ns	6.10ns	9.37ns
1k	2.67ns	1.87ns	22.71ns	1.26ns	5.21ns	3.99ns	3.47ns
16k	1.95ns	0.99ns	29.90ns	0.90ns	5.08ns	3.29ns	1.54ns
256k	1.78ns	0.83ns	67.57ns	0.82ns	5.05ns	3.18ns	1.28ns
1M	1.84ns	1.08ns	95.13ns	1.23ns	5.06ns	3.20ns	1.37ns

Note: Donburi, GOKe, unitoftime/ecs, and Volt use a callback-based approach for their query loops. As a result, iteration speed may degrade if the callback contains complex logic and the Go compiler is unable to inline it.

Query fragmented, outer

Query where there are 256 non-matching archetypes.

N entities with components Position and Velocity. Another 4 * N entities with Position and some combination of 8 components C1, ..., C8, so these entities are fragmented over up to 256 archetypes.

• Query all [Position, Velocity] entities, and add the velocity vector to the position vector.

N	Ark	Ark (tables)	Donburi	ggecs	GOKe	uot	Volt
1	62.22ns	68.11ns	63.51ns	55.53ns	21.48ns	17.18ns	100.59ns
4	17.44ns	17.50ns	29.59ns	25.96ns	18.81ns	9.72ns	47.94ns
16	5.69ns	4.96ns	21.19ns	19.01ns	25.46ns	4.73ns	36.19ns
64	2.73ns	1.93ns	19.45ns	16.96ns	29.94ns	3.79ns	37.37ns
256	2.01ns	1.07ns	20.15ns	8.13ns	12.01ns	3.38ns	10.51ns
1k	1.91ns	0.89ns	20.08ns	5.80ns	9.16ns	3.17ns	3.57ns
16k	1.93ns	0.82ns	20.82ns	5.11ns	3.91ns	3.18ns	1.45ns
256k	1.96ns	0.80ns	23.61ns	5.06ns	6.24ns	3.17ns	1.28ns
1M	2.03ns	1.17ns	27.19ns	5.10ns	6.93ns	3.20ns	1.41ns

Note: Donburi, GOKe, unitoftime/ecs, and Volt use a callback-based approach for their query loops. As a result, iteration speed may degrade if the callback contains complex logic and the Go compiler is unable to inline it.

Component random access

N entities with component Position. All entities are collected into a slice, and the slice is shuffled.

• Iterate the shuffled entities.
• For each entity, get its Position and sum up their X fields.

N	Ark	Donburi	GOKe	ggecs	uot	Volt
1	3.03ns	9.42ns	16.55ns	9.32ns	39.12ns	13.73ns
4	2.87ns	8.99ns	9.12ns	9.25ns	38.88ns	13.49ns
16	2.96ns	8.57ns	6.22ns	14.28ns	39.58ns	12.89ns
64	3.05ns	8.65ns	5.73ns	14.42ns	42.86ns	12.99ns
256	3.18ns	9.83ns	6.22ns	16.21ns	43.74ns	13.26ns
1k	2.99ns	15.08ns	6.03ns	19.51ns	43.06ns	13.52ns
16k	6.20ns	45.13ns	12.88ns	36.85ns	68.22ns	17.86ns
256k	9.15ns	165.38ns	19.22ns	118.57ns	164.13ns	25.43ns
1M	48.20ns	277.23ns	85.79ns	180.91ns	253.13ns	118.56ns

Create entities

• Create N entities with components Position and Velocity.

The operation is performed once before benchmarking, to exclude memory allocation, archetype creation etc. See the benchmark below for entity creation with allocation.

N	Ark	Ark (batch)	Donburi	ggecs	GOKe	uot	Volt
1	235.14ns	263.06ns	1.25us	442.41ns	254.34ns	488.68ns	726.32ns
4	86.04ns	73.56ns	503.18ns	175.09ns	100.07ns	207.12ns	268.66ns
16	46.61ns	25.41ns	328.37ns	142.33ns	67.66ns	132.84ns	148.35ns
64	35.31ns	12.73ns	274.88ns	133.48ns	60.88ns	107.74ns	135.57ns
256	30.88ns	10.09ns	205.76ns	111.91ns	54.11ns	99.04ns	92.58ns
1k	30.39ns	10.29ns	191.49ns	110.87ns	49.71ns	360.79ns	87.01ns
16k	23.06ns	8.21ns	207.83ns	117.70ns	51.25ns	352.05ns	84.02ns
256k	22.70ns	8.25ns	216.70ns	132.35ns	50.38ns	412.51ns	83.55ns
1M	22.83ns	8.43ns	183.99ns	226.05ns	50.75ns	465.49ns	83.62ns

Create entities, allocating

• Create N entities with components Position and Velocity.

Each round is performed on a fresh world. This reflects the creation of the first entities with a certain components set in your game or application. As soon as things stabilize, the benchmarks for entity creation without allocation (above) apply.

Low N values might be biased by things like archetype creation and memory allocation, which is handled differently by different implementations.

N	Ark	Ark (batch)	Donburi	GOKe	ggecs	uot	Volt
1	8.77us	8.83us	5.55us	694.23ns	21.77us	3.53us	1.52us
4	2.26us	2.32us	1.64us	225.30ns	4.95us	1.21us	655.55ns
16	601.53ns	564.16ns	656.56ns	110.01ns	1.68us	409.25ns	275.95ns
64	176.66ns	154.87ns	435.00ns	72.27ns	598.60ns	227.93ns	169.58ns
256	71.05ns	48.73ns	329.15ns	62.45ns	274.29ns	181.97ns	151.35ns
1k	42.87ns	22.29ns	311.29ns	60.22ns	240.93ns	166.74ns	125.64ns
16k	51.97ns	43.27ns	432.03ns	58.67ns	257.71ns	208.14ns	152.06ns
256k	63.64ns	33.21ns	490.25ns	61.21ns	590.99ns	213.69ns	146.03ns
1M	41.78ns	21.55ns	438.47ns	55.87ns	1.13us	271.69ns	122.60ns

Create large entities

• Create N entities with 10 components C1, ..., C10.

The operation is performed once before benchmarking, to exclude things like archetype creation and memory allocation.

N	Ark	Ark (batch)	Donburi	ggecs	GOKe	uot	Volt
1	271.74ns	231.29ns	2.05us	552.75ns	288.18ns	755.48ns	2.69us
4	94.90ns	64.02ns	1.29us	244.37ns	134.83ns	397.72ns	1.52us
16	45.79ns	22.55ns	1.07us	213.33ns	100.37ns	276.22ns	1.22us
64	35.34ns	12.76ns	846.41ns	221.80ns	89.94ns	261.02ns	967.33ns
256	30.04ns	10.19ns	732.01ns	162.32ns	78.07ns	209.06ns	911.42ns
1k	30.64ns	9.21ns	733.47ns	165.32ns	105.08ns	477.30ns	906.52ns
16k	23.03ns	7.91ns	744.09ns	167.40ns	90.14ns	485.23ns	919.34ns
256k	25.03ns	8.02ns	730.01ns	186.51ns	77.34ns	597.62ns	879.88ns
1M	23.57ns	7.92ns	755.32ns	254.82ns	78.66ns	712.05ns	884.82ns

Add/remove component

N entities with component Position.

• Add Velocity to all entities.
• Remove Velocity from all entities.

One iteration is performed before the benchmarking starts, to exclude memory allocation.

N	Ark	Ark (batch)	Donburi	ggecs	GOKe	uot	Volt
1	94.26ns	175.26ns	424.22ns	551.07ns	100.93ns	346.14ns	269.01ns
4	103.06ns	46.05ns	434.91ns	517.98ns	117.61ns	368.82ns	288.90ns
16	116.21ns	22.96ns	461.93ns	576.86ns	115.58ns	379.05ns	275.31ns
64	119.30ns	13.88ns	478.17ns	586.26ns	130.25ns	390.33ns	281.29ns
256	113.32ns	9.47ns	500.93ns	634.93ns	133.44ns	442.01ns	346.19ns
1k	121.67ns	9.69ns	484.85ns	606.05ns	111.59ns	776.23ns	273.92ns
16k	107.45ns	10.08ns	510.57ns	618.32ns	124.08ns	847.29ns	272.76ns
256k	120.70ns	12.16ns	519.11ns	919.32ns	120.93ns	1.31us	282.73ns
1M	115.79ns	12.08ns	497.45ns	1.08us	126.40ns	1.46us	269.10ns

Add/remove component, large entity

N entities with component Position and 10 further components C1, ..., C10.

• Add Velocity to all entities.
• Remove Velocity from all entities.

One iteration is performed before the benchmarking starts, to exclude memory allocation.

N	Ark	Ark (batch)	Donburi	ggecs	GOKe	uot	Volt
1	344.97ns	459.63ns	1.10us	969.83ns	271.90ns	803.15ns	1.50us
4	401.62ns	122.81ns	1.14us	988.26ns	372.31ns	823.58ns	1.41us
16	405.94ns	47.65ns	1.09us	1.05us	356.68ns	812.59ns	1.41us
64	412.96ns	28.32ns	1.09us	1.06us	356.92ns	879.76ns	1.41us
256	409.67ns	22.54ns	1.11us	1.07us	392.21ns	994.47ns	1.61us
1k	431.39ns	20.96ns	1.24us	1.01us	425.42ns	1.51us	1.46us
16k	423.38ns	26.64ns	1.27us	1.24us	500.33ns	1.78us	1.60us
256k	593.08ns	45.17ns	1.52us	1.63us	445.56ns	2.16us	1.65us
1M	495.37ns	44.80ns	1.58us	1.85us	523.10ns	2.48us	1.87us

Delete entities

N entities with components Position and Velocity.

• Delete all entities

N	Ark	Ark (batch)	Donburi	GOKe	ggecs	uot	Volt
1	140.62ns	243.47ns	221.33ns	166.36ns	340.23ns	164.53ns	290.58ns
4	72.64ns	66.18ns	94.26ns	90.07ns	172.72ns	73.49ns	121.19ns
16	46.11ns	21.11ns	72.01ns	65.92ns	157.56ns	54.96ns	101.00ns
64	37.75ns	8.73ns	57.01ns	59.94ns	122.81ns	46.59ns	76.73ns
256	28.45ns	7.30ns	45.81ns	43.72ns	110.68ns	40.08ns	53.74ns
1k	28.61ns	5.66ns	38.58ns	29.63ns	93.75ns	32.88ns	55.87ns
16k	22.62ns	4.04ns	42.36ns	30.37ns	101.84ns	37.76ns	54.01ns
256k	23.27ns	4.98ns	42.23ns	31.82ns	241.90ns	80.78ns	51.83ns
1M	25.69ns	6.24ns	55.25ns	33.51ns	323.32ns	129.66ns	56.58ns

Delete large entities

N entities with 10 components C1, ..., C10.

• Delete all entities

N	Ark	Ark (batch)	Donburi	ggecs	GOKe	uot	Volt
1	197.78ns	303.94ns	402.98ns	483.48ns	232.17ns	154.54ns	540.20ns
4	136.65ns	80.35ns	200.80ns	297.14ns	162.98ns	72.85ns	455.88ns
16	147.44ns	28.79ns	171.13ns	260.05ns	147.26ns	48.67ns	322.51ns
64	100.46ns	14.86ns	134.78ns	169.22ns	93.72ns	49.54ns	234.96ns
256	75.88ns	8.60ns	107.21ns	142.86ns	89.24ns	42.57ns	212.31ns
1k	69.26ns	7.61ns	104.43ns	144.76ns	85.37ns	34.32ns	289.04ns
16k	66.49ns	9.91ns	107.97ns	166.74ns	77.57ns	33.49ns	206.58ns
256k	75.69ns	13.74ns	150.44ns	342.90ns	88.27ns	78.40ns	207.33ns
1M	71.36ns	16.68ns	238.52ns	429.94ns	92.04ns	122.24ns	211.13ns

Create world

• Create a new world

N	Ark	Donburi	GOKe	ggecs	uot	Volt
1	30.52us	3.34us	500.12us	307.36us	3.24us	28.65us

Popularity

Given that all tested projects are on Github, we can use the star history as a proxy here.

Running the benchmarks

Run the benchmarks using the following command:

go run . -test.benchtime=0.25s

On PowerShell use this instead:
go run . --% -test.benchtime=0.25s

The benchtime limit is required for some of the benchmarks that have a high setup cost which is not timed. They would take forever otherwise. The benchmarks can take up to one hour to complete.

To run a selection of benchmarks, add their names as arguments:

go run . query2comp query32arch

To create the plots, run plot/plot.py. The following packages are required:

• numpy
• pandas
• matplotlib

pip install -r ./plot/requirements.txt
python plot/plot.py

Contributing

Developers of ECS frameworks are welcome to add their implementation to the benchmarks. However, there are a few (quality) criteria that need to be fulfilled for inclusion:

• All benchmarks must be implemented, which means that the ECS must have the required features
• The ECS must be working properly and not exhibit serious flaws; it will undergo a basic review by maintainers
• The ECS must be sufficiently documented so that it can be used without reading the code
• There must be at least basic unit tests
• Unit tests must be run in the CI of the repository
• The ECS must not be tightly coupled to a particular game engine, particularly graphics stuff
• There must be tagged release versions; only tagged versions will be included here

Developers of included frameworks are encouraged to review the benchmarks, and to fix (or point to) misuse or potential optimizations.