Swift versus Java 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. mandelbrot source secs mem gz busy cpu load Swift 3.20 39,320 1138 12.68 99% 100% 99% 99% Java 6.84 76,008 796 26.90 99% 98% 98% 98% fannkuch-redux source secs mem gz busy cpu load Swift 10.08 8,028 1097 39.99 98% 100% 99% 100% Java 16.12 33,168 1282 63.71 100% 98% 99% 98% pidigits source secs mem gz busy cpu load Swift 1.75 8,716 600 2.05 5% 100% 12% 1% Java 1.83 34,848 764 1.95 99% 1% 4% 2% spectral-norm source secs mem gz busy cpu load Swift 3.99 7,836 601 15.93 100% 100% 100% 100% Java 4.15 36,428 950 16.26 98% 100% 98% 97% n-body source secs mem gz busy cpu load Swift 21.74 12,092 1355 22.86 1% 2% 100% 2% Java 21.85 34,112 1489 22.16 1% 0% 0% 100% reverse-complement source secs mem gz busy cpu load Swift 3.79 753,924 1286 4.83 7% 70% 12% 39% Java 3.27 714,144 2183 7.54 47% 60% 66% 58% fasta source secs mem gz busy cpu load Swift 2.91 8,524 1945 4.59 18% 62% 63% 14% Java 2.22 43,096 2473 6.10 67% 83% 45% 80% k-nucleotide source secs mem gz busy cpu load Swift 22.39 257,104 1367 84.59 94% 96% 93% 95% Java 9.14 403,576 1812 29.10 87% 72% 74% 86% regex-redux source secs mem gz busy cpu load Swift 44.59 885,164 715 81.94 19% 60% 20% 85% Java 10.27 635,500 740 29.42 74% 81% 55% 76% binary-trees source secs mem gz busy cpu load Swift 38.21 702,592 816 122.34 76% 70% 79% 95% Java 8.28 948,040 835 28.20 80% 84% 87% 90% Swift Swift version 5.1.3 (swift-5.1.3-RELEASE) Target: x86_64-unknown-linux-gnu Java openjdk 14 2020-03-17 OpenJDK Runtime Environment (build 14+36-1461) OpenJDK 64-Bit Server VM (build 14+36-1461, mixed mode, sharing) all Swift programs & measurements all Java programs & measurements