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 1.87 39,072 1138 7.44 100% 99% 98% 99% Java 4.11 68,204 796 16.20 98% 99% 98% 99% fannkuch-redux source secs mem gz busy cpu load Swift 7.46 7,668 1097 29.52 98% 100% 99% 100% Java 11.00 34,104 1282 43.42 99% 98% 98% 99% n-body source secs mem gz busy cpu load Swift 4.89 10,240 1326 4.95 0% 100% 1% 0% Java 6.75 35,200 1489 6.83 0% 0% 100% 1% spectral-norm source secs mem gz busy cpu load Swift 1.44 7,960 601 5.73 100% 99% 100% 99% Java 1.68 38,348 950 6.43 96% 96% 96% 95% pidigits source secs mem gz busy cpu load Swift 0.76 8,428 600 0.82 100% 3% 1% 4% Java 0.79 35,568 764 0.84 99% 3% 3% 1% reverse-complement source secs mem gz busy cpu load Swift 1.79 788,908 1286 2.25 74% 19% 2% 30% Java 1.54 702,332 2183 3.55 78% 46% 49% 57% fasta source secs mem gz busy cpu load Swift 1.51 26,104 2090 4.81 91% 76% 77% 74% Java 1.27 43,968 2473 3.92 73% 95% 70% 70% k-nucleotide source secs mem gz busy cpu load Swift 14.26 256,316 1367 54.61 97% 95% 95% 96% Java 5.00 408,040 1812 16.36 74% 81% 86% 86% regex-redux source secs mem gz busy cpu load Swift 24.30 1,060,320 745 50.20 44% 92% 35% 35% Java 5.70 656,328 929 18.25 89% 76% 79% 75% binary-trees source secs mem gz busy cpu load Swift 16.00 699,652 862 50.97 100% 65% 76% 78% Java 2.50 2,487,096 835 7.90 88% 75% 75% 79% Swift Swift version 5.3 (swift-5.3-RELEASE) Target: x86_64-unknown-linux-gnu Java openjdk 15 2020-09-15 OpenJDK Runtime Environment (build 15+36-1562) OpenJDK 64-Bit Server VM (build 15+36-1562, mixed mode, sharing) all Swift programs & measurements all Java programs & measurements