Swift versus Rust fastest performance

How the programs are written matters! Always look at the source code.

If the fastest programs are hand-written vector instructions, does the host language matter? You might be more interested in the less optimised programs — more seconds, less gz source code.

fannkuch-redux
source	secs	mem	gz	cpu secs
Rust #6	3.92	19,072	1260	15.36
Rust #4	6.96	19,072	1026	27.18
Rust #5	7.72	19,072	1023	30.41
Swift	33.92	19,656	457	33.91
Swift #3	8.57	19,656	1103	33.94
Rust #2	9.42	19,072	1198	36.90
n-body
source	secs	mem	gz	cpu secs
Rust #9	2.17	19,072	1881	2.17
Rust #7	3.24	19,072	1759	3.24
Rust #2	3.94	19,072	1809	3.94
Rust #6	4.31	19,072	1796	4.30
Rust #8	4.49	19,072	1774	4.49
Rust #5	5.01	19,072	2224	5.01
Rust #4	5.17	19,072	1810	5.17
Swift #4	5.49	19,688	1361	5.49
Rust	5.51	19,072	1483	5.51
Swift #5	5.52	19,688	1372	5.52
Swift #7	5.54	19,700	1333	5.54
Rust #3	5.55	19,072	1546	5.55
Swift #6	5.99	19,700	1200	5.99
Swift #8	6.00	19,684	1688	5.99
Swift #3	8.12	19,688	1210	8.12
Swift #2	9.54	19,684	1198	9.54
Swift #9	287.21	19,688	1532	287.20
spectral-norm
source	secs	mem	gz	cpu secs
Rust #4	0.72	19,076	823	2.85
Rust #6	0.72	19,076	1132	2.85
Rust #5	0.72	19,076	1062	2.85
Rust #7	0.72	19,076	938	2.85
Rust #2	0.78	19,076	1117	3.03
Rust	0.79	19,076	1262	3.04
Rust #3	0.92	19,076	1060	3.57
Swift	5.33	20,308	444	5.33
Swift #3	1.43	20,084	607	5.69
mandelbrot
source	secs	mem	gz	cpu secs
Rust #4	0.94	33,280	1301	3.73
Rust #6	1.08	34,048	1338	4.22
Rust #7	1.06	33,280	763	4.22
Rust #8	1.06	33,280	770	4.22
Rust #5	1.13	33,792	725	4.45
Rust #3	1.14	19,072	1013	4.54
Swift #7	1.34	47,104	1147	5.30
Swift #6	1.45	50,048	1147	5.75
Rust	2.03	39,168	874	7.89
Swift	26.47	19,664	400	26.47
Swift #5	7.24	43,392	665	27.01
Swift #3		Bad Output
pidigits
source	secs	mem	gz	cpu secs
Rust #4	0.71	19,076	804	0.71
Rust #3	0.74	19,076	1373	0.74
Rust	0.74	19,076	1426	0.74
Rust #2	0.75	19,076	1312	0.75
Swift #2	0.89	19,700	606	0.89
regex-redux
source	secs	mem	gz	cpu secs
Rust #6	1.19	153,456	994	1.45
Rust #5	1.31	202,588	777	1.56
Rust	1.34	153,776	811	1.58
Rust #4	1.34	199,540	771	1.60
Rust #2	1.35	153,780	707	1.60
Rust #3	1.36	202,904	726	1.62
Rust #7	0.78	151,040	2464	1.99
Swift #2	42.42	684,644	678	42.42
Swift	24.44	889,924	721	43.38
Swift #4	20.99	1,055,220	751	44.94
fasta
source	secs	mem	gz	cpu secs
Rust #7	0.77	19,072	2533	1.54
Rust #3	1.99	19,072	1235	1.99
Rust #8	0.92	19,072	1952	3.11
Rust #5	0.93	19,072	1963	3.37
Rust #2	0.94	19,072	1910	3.37
Rust #6	3.47	123,656	959	3.46
Rust #4	3.58	123,656	944	3.58
Rust	4.21	19,072	1240	4.21
Swift #2	3.14	19,664	1952	5.14
Swift	5.16	19,664	1533	5.16
Swift #3	2.18	29,456	2097	5.35
k-nucleotide
source	secs	mem	gz	cpu secs
Rust #7	2.84	133,808	1585	8.92
Rust #8	3.55	137,360	1549	10.66
Rust #6	3.00	159,596	1697	10.88
Rust #5	3.96	137,896	1745	11.92
Rust #2	6.37	137,736	1350	16.21
Rust #9	6.36	135,720	1850	17.37
Rust #4	6.64	137,260	1755	17.99
Swift #2	14.61	259,048	1373	55.63
Rust	22.12	157,252	1086	66.01
Swift		Make Error
reverse-complement
source	secs	mem	gz	cpu secs
Rust	0.53	498,816	2762	0.83
Rust #2	0.96	995,072	1332	1.59
Rust #3	0.98	995,200	1105	1.70
Swift	1.95	796,836	1293	2.38
binary-trees
source	secs	mem	gz	cpu secs
Rust #5	1.05	198,528	771	3.67
Rust #2	1.20	199,556	729	4.26
Rust #4	1.35	198,900	765	4.88
Rust #3	1.43	193,728	762	5.15
Rust	2.07	132,736	760	7.36
Swift #5	14.19	736,000	813	42.47
Swift #2	13.67	705,152	822	43.96
Swift #3	13.67	705,408	868	44.28
Swift	20.52	735,360	720	60.79
Swift #4	19.86	705,280	772	63.33
Swift #9		Make Error
Swift	Swift version 5.10 (swift-5.10-RELEASE)
Rust	1.79.0 (129f3b996 2024-06-10) LLVM version: 18.1.7