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	4.00	19,652	1260	15.86
Rust #4	7.10	19,652	1026	27.94
Rust #5	7.88	19,784	1023	30.85
Swift	33.85	19,660	457	33.85
Swift #3	8.58	19,660	1103	33.96
Rust #2	18.53	19,780	1198	73.32
n-body
source	secs	mem	gz	cpu secs
Rust #9	2.20	19,660	1881	2.20
Rust #7	3.13	19,660	1759	3.13
Rust #2	3.92	19,660	1809	3.92
Rust #6	3.95	19,788	1796	3.95
Rust #8	4.51	19,788	1774	4.50
Rust #5	5.06	19,788	2224	5.06
Rust #4	5.21	19,660	1810	5.21
Swift #4	5.49	19,680	1361	5.49
Rust	5.51	19,660	1483	5.51
Swift #5	5.51	19,812	1372	5.51
Swift #7	5.52	19,684	1333	5.52
Rust #3	5.60	19,656	1546	5.60
Swift #6	5.97	19,680	1200	5.97
Swift #8	5.99	19,808	1688	5.99
Swift #2	9.55	19,684	1198	9.55
Swift #3	202.89	19,680	1210	202.89
Swift #9	287.28	19,684	1532	287.27
spectral-norm
source	secs	mem	gz	cpu secs
Rust #2	0.72	19,668	1117	2.58
Rust	0.74	19,668	1262	2.60
Rust #3	0.79	19,796	1060	2.83
Rust #6	0.72	19,668	1132	2.84
Rust #4	0.72	19,796	823	2.85
Rust #7	0.72	19,796	938	2.85
Rust #5	0.72	19,668	1062	2.85
Swift	5.32	19,684	444	5.32
Swift #3	1.43	19,684	607	5.69
mandelbrot
source	secs	mem	gz	cpu secs
Rust #4	0.96	33,280	1301	3.78
Rust #6	1.07	34,048	1338	4.20
Rust #8	1.06	33,280	770	4.21
Rust #7	1.06	33,280	763	4.21
Rust #5	1.12	33,920	725	4.40
Rust #3	1.14	19,656	1013	4.51
Swift #7	1.34	47,104	1147	5.30
Swift #6	1.45	50,176	1147	5.73
Rust	1.83	39,296	874	7.20
Swift	26.40	19,680	400	26.40
Swift #5	7.21	43,520	665	26.95
Swift #3		Bad Output
pidigits
source	secs	mem	gz	cpu secs
Rust #4	0.71	19,660	804	0.71
Rust	0.88	19,660	1426	0.88
Rust #3	0.88	19,660	1373	0.88
Rust #2	0.88	19,660	1312	0.88
Swift #2	0.88	19,684	606	0.88
regex-redux
source	secs	mem	gz	cpu secs
Rust #6	1.19	153,584	994	1.44
Rust #5	1.28	202,584	777	1.52
Rust	1.30	154,416	811	1.52
Rust #4	1.30	199,540	771	1.54
Rust #3	1.31	202,684	726	1.56
Rust #2	1.34	153,896	707	1.58
Rust #7	0.78	150,272	2464	1.99
Swift #2	41.76	684,640	678	41.75
Swift	24.13	889,972	721	42.70
Swift #4	20.41	1,060,208	751	44.32
fasta
source	secs	mem	gz	cpu secs
Rust #7	0.76	19,664	2533	1.51
Rust #3	2.00	19,656	1235	2.00
Rust #8	0.92	19,784	1952	3.10
Rust #2	0.91	19,656	1910	3.29
Rust #5	0.91	19,656	1963	3.30
Rust #4	3.45	123,784	944	3.45
Rust #6	3.48	123,784	959	3.48
Swift #2	2.18	19,680	1952	3.83
Rust	4.52	19,656	1240	4.52
Swift	5.15	19,676	1533	5.15
Swift #3	2.14	29,584	2097	5.26
k-nucleotide
source	secs	mem	gz	cpu secs
Rust #7	2.86	134,084	1585	9.12
Rust #8	3.68	137,580	1549	10.41
Rust #6	2.90	159,464	1697	10.51
Rust #5	3.91	137,764	1745	11.86
Rust #2	6.10	139,388	1350	16.32
Rust #9	6.77	135,684	1850	18.07
Rust #4	6.70	137,288	1755	18.12
Swift #2	14.51	259,048	1373	55.29
Rust	21.62	157,080	1086	64.67
Swift		Make Error
reverse-complement
source	secs	mem	gz	cpu secs
Rust	0.52	498,816	2762	0.83
Rust #2	0.85	995,200	1332	1.50
Rust #3	0.87	995,072	1105	1.58
Swift	1.88	796,840	1293	2.30
binary-trees
source	secs	mem	gz	cpu secs
Rust #5	1.08	198,528	771	3.82
Rust #2	1.22	199,676	729	4.29
Rust #4	1.29	189,052	765	4.67
Rust #3	1.39	198,860	762	5.04
Rust	2.04	133,120	760	7.21
Swift #5	13.79	736,000	813	40.99
Swift #3	13.33	705,408	868	43.00
Swift #2	13.28	705,280	822	43.28
Swift	20.15	735,488	720	59.68
Swift #4	19.49	705,536	772	62.34
Swift #9		Make Error
Swift	Swift version 5.10 (swift-5.10-RELEASE)
Rust	1.76.0 (07dca489a 2024-02-04) LLVM version: 17.0.6