Swift versus Rust fastest programs Always look at the source code. These are only the fastest programs. Look at the other programs. They may seem more-like a fair comparison to you. fannkuch-redux source secs mem gz busy cpu load Swift 10.08 8,028 1097 39.99 98% 100% 99% 100% Rust 10.06 1,020 1016 39.36 93% 100% 100% 99% pidigits source secs mem gz busy cpu load Swift 1.75 8,716 600 2.05 5% 100% 12% 1% Rust 1.75 3,012 1366 1.78 1% 100% 1% 0% mandelbrot source secs mem gz busy cpu load Swift 3.20 39,320 1138 12.68 99% 100% 99% 99% Rust 1.70 32,656 1332 6.70 98% 98% 99% 98% fasta source secs mem gz busy cpu load Swift 2.91 8,524 1945 4.59 18% 62% 63% 14% Rust 1.51 2,180 1906 4.66 76% 76% 83% 74% spectral-norm source secs mem gz busy cpu load Swift 3.99 7,836 601 15.93 100% 100% 100% 100% Rust 1.97 2,440 1126 7.86 100% 99% 99% 99% reverse-complement source secs mem gz busy cpu load Swift 3.79 753,924 1286 4.83 7% 70% 12% 39% Rust 1.69 994,988 1330 2.95 26% 45% 79% 24% n-body source secs mem gz busy cpu load Swift 21.74 12,092 1355 22.86 1% 2% 100% 2% Rust 5.98 688 1753 6.02 0% 1% 100% 0% k-nucleotide source secs mem gz busy cpu load Swift 22.39 257,104 1367 84.59 94% 96% 93% 95% Rust 5.21 135,388 1841 15.94 82% 54% 100% 70% binary-trees source secs mem gz busy cpu load Swift 38.21 702,592 816 122.34 76% 70% 79% 95% Rust 3.48 199,856 721 12.62 88% 100% 87% 88% regex-redux source secs mem gz busy cpu load Swift 44.59 885,164 715 81.94 19% 60% 20% 85% Rust 2.20 153,504 986 3.23 15% 32% 84% 16% Swift Swift version 5.1.3 (swift-5.1.3-RELEASE) Target: x86_64-unknown-linux-gnu Rust rustc 1.44.0 (49cae5576 2020-06-01) LLVM version: 9.0 all Swift programs & measurements all Rust programs & measurements