gobitmapbenchmark

August 22, 2026 · View on GitHub

A Go program to compare bitmap implementations. This is not a library.

It measures uncompressed bitsets and two Roaring Bitmap implementations: a pure-Go port, and a cgo wrapper around CRoaring.

Implementations

Package	Notes
github.com/bits-and-blooms/bitset	Uncompressed bitset (formerly `github.com/willf/bitset`)
github.com/RoaringBitmap/roaring/v2	Pure Go Roaring bitmaps
github.com/RoaringBitmap/gocroaring	cgo wrapper for CRoaring

The older goroar implementation is no longer included. It has been unmaintained since 2014.

Requirements

Go 1.24 or later
A C compiler (gocroaring uses cgo)

go test -count=1

Usage

Synthetic microbenchmarks (intersection, union, set, contains, count, iterate):

go test -bench . -run '^$' -skip Real -benchmem

Real datasets under realdata/ (census, weather, wikileaks, and sorted variants):

go test -bench BenchmarkReal -run '^$' -benchmem

Serialized size of two random sets (N1=650000 values in [0, 15000000) and N2=650000 values in [0, 100000000)):

go test -run TestSize -v

The real-data files are comma-separated 32-bit integer sets. See realdata/README.md.

Recorded with Go 1.24.3 on an Apple M4 Max (darwin/arm64), using bitset v1.25.0, roaring/v2 v2.25.0, and gocroaring v1.0.0 (CRoaring 4.5.0). Numbers are illustrative; run the commands above on your machine.

Serialized size (`TestSize`)

Implementation	Size
bitset	13.709 MB
roaring	2.462 MB
gocroaring	2.463 MB

Synthetic

Time (ns/op):

Benchmark	bitset	roaring	gocroaring
Intersection	209,236	745,625	719,899
IntersectionDense	26,519	63,484	45,144
Union	801,288	994,885	921,073
Set	3.320	18.84	49.41
Contains	3.291	51.57	81.81
Count	3,554	14.76	33.02
Iterate	161,471	246,312	1,714,062
SparseIterate	878,637	196,074	2,041,873

Memory (B/op / allocs/op):

Benchmark	bitset	roaring	gocroaring
Intersection	1,876,006 / 2	224,169 / 481	8 / 1
IntersectionDense	188,449 / 2	113,560 / 60	8 / 1
Union	12,501,031 / 2	2,792,967 / 3,086	8 / 1
Set	0 / 0	0 / 0	4 / 1
Contains	0 / 0	0 / 0	0 / 0
Count	0 / 0	0 / 0	0 / 0
Iterate	0 / 0	112 / 1	16 / 1
SparseIterate	0 / 0	112 / 1	16 / 1

Real data

Each table compares pure-Go roaring with cgo gocroaring on one dataset.

census-income

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	16,589,097	16,199,160	9,031,890	3,392	9,330	201
clone	342,794	326,833	2,353,336	3,392	2,537	201
iterate	31,280,922	213,813,408	22,400	3,200	200	200
toArray	5,879,046	4,960,540	28,083,329	28,083,321	201	201
pairwise AND	1,584,371	1,211,460	3,065,401	1,592	3,824	199
pairwise OR	1,532,910	1,248,313	3,624,378	1,592	2,808	199
fast OR	389,339	324,923	42,464	1,800	24	2

census-income_srt

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	15,796,842	14,681,891	9,082,342	3,392	10,076	201
clone	121,144	194,735	540,376	3,392	2,383	201
iterate	21,827,623	188,387,396	22,400	3,200	200	200
toArray	3,729,085	3,169,311	24,748,397	24,748,372	201	201
pairwise AND	451,692	339,413	647,613	1,592	3,567	199
pairwise OR	5,222,479	772,519	27,072,048	1,592	19,157	199
fast OR	178,874	126,711	53,056	1,800	29	2

census1881

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	3,500,324	3,553,999	6,499,942	3,392	12,940	201
clone	338,981	354,890	2,103,482	3,392	3,929	201
iterate	2,979,836	31,061,332	22,400	3,200	200	200
toArray	598,546	495,695	4,068,245	4,068,240	200	200
pairwise AND	26,135	159,061	45,864	1,592	450	199
pairwise OR	3,882,382	1,132,140	23,262,300	1,592	18,938	199
fast OR	2,608,709	671,615	2,018,879	1,800	464	2

census1881_srt

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	2,842,899	2,414,933	2,213,217	3,392	16,165	201
clone	131,131	235,569	316,173	3,392	6,077	201
iterate	2,745,233	21,508,570	22,400	3,200	200	200
toArray	545,365	470,329	2,776,355	2,776,353	200	200
pairwise AND	21,580	164,361	39,888	1,592	923	199
pairwise OR	330,432	351,363	707,542	1,592	12,068	199
fast OR	627,913	255,945	821,871	1,800	561	2

uscensus2000

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	167,577	324,584	233,298	3,392	6,342	201
clone	82,810	233,873	145,289	3,392	5,443	201
iterate	36,179	293,381	22,400	3,200	200	200
toArray	14,464	22,502	25,968	25,968	200	200
pairwise AND	6,680	156,677	16,482	1,592	241	199
pairwise OR	196,919	334,682	411,597	1,592	10,724	199
fast OR	109,795	487,362	65,832	1,800	1,700	2

weather_sept_85

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	34,691,750	34,815,911	32,349,597	3,392	30,529	201
clone	1,136,505	2,247,517	9,054,955	3,392	6,713	201
iterate	56,461,092	402,331,667	22,400	3,200	200	200
toArray	11,228,982	10,445,023	51,990,914	51,990,902	200	200
pairwise AND	5,280,902	4,825,924	3,543,417	1,592	6,194	199
pairwise OR	5,703,905	5,320,256	15,048,226	1,592	8,606	199
fast OR	2,003,237	1,827,189	132,720	1,800	73	2

weather_sept_85_srt

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	42,762,407	40,305,885	26,052,229	3,392	27,368	201
clone	271,905	323,073	838,615	3,392	5,337	201
iterate	57,588,646	498,351,903	22,400	3,200	200	200
toArray	8,684,755	8,600,311	64,914,541	64,914,419	202	201
pairwise AND	811,007	534,931	588,663	1,592	6,350	199
pairwise OR	3,028,185	1,060,899	7,484,388	1,592	20,812	199
fast OR	124,608	56,112	146,346	1,800	177	2

wikileaks-noquotes

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	2,440,103	1,882,933	2,238,945	3,392	21,541	201
clone	118,397	268,028	311,308	3,392	4,785	201
iterate	1,344,585	8,840,031	22,400	3,200	200	200
toArray	382,020	343,992	1,168,516	1,168,522	200	200
pairwise AND	165,292	299,451	86,280	1,592	2,220	199
pairwise OR	1,400,975	448,117	4,754,722	1,592	21,235	199
fast OR	110,944	72,997	186,713	1,800	101	2

wikileaks-noquotes_srt

Operation	roaring ns/op	gocroaring ns/op	roaring B/op	gocroaring B/op	roaring allocs	gocroaring allocs
creating	1,489,074	1,534,888	1,487,453	3,392	14,566	201
clone	73,449	247,063	149,913	3,392	4,151	201
iterate	1,122,314	8,933,274	22,400	3,200	200	200
toArray	234,169	219,990	1,206,259	1,206,261	200	200
pairwise AND	50,258	248,177	69,040	1,592	1,485	199
pairwise OR	3,046,920	363,320	18,377,363	1,592	19,775	199
fast OR	105,923	55,411	296,074	1,800	345	2