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 3.19 39,296 1138 12.65 99% 99% 100% 99% Java 6.83 79,108 796 26.86 97% 99% 99% 99% pidigits source secs mem gz busy cpu load Swift 1.75 8,828 600 1.78 2% 0% 1% 99% Java 3.07 39,320 938 3.31 2% 5% 3% 98% fannkuch-redux source secs mem gz busy cpu load Swift 10.01 7,436 1097 39.63 99% 98% 100% 100% Java 14.33 34,888 1282 56.56 99% 98% 99% 98% spectral-norm source secs mem gz busy cpu load Swift 3.96 8,000 601 15.79 100% 100% 100% 100% Java 4.22 36,948 950 16.43 98% 97% 98% 96% n-body source secs mem gz busy cpu load Swift 22.03 12,160 1355 22.25 0% 0% 100% 1% Java 21.93 35,408 1429 22.44 1% 0% 100% 1% reverse-complement source secs mem gz busy cpu load Swift 3.84 720,884 1286 4.61 2% 1% 81% 36% Java 3.16 712,368 2183 7.08 65% 47% 42% 70% fasta source secs mem gz busy cpu load Swift 3.02 8,720 1945 4.64 20% 39% 47% 48% Java 2.22 45,172 2473 5.99 61% 50% 98% 60% k-nucleotide source secs mem gz busy cpu load Swift 21.98 257,192 1367 83.02 93% 94% 93% 97% Java 9.33 447,976 1812 29.36 73% 83% 82% 77% regex-redux source secs mem gz busy cpu load Swift 44.49 881,444 715 80.43 26% 92% 1% 62% Java 10.31 644,560 740 31.47 72% 72% 92% 70% binary-trees source secs mem gz busy cpu load Swift 37.86 702,792 816 119.21 100% 76% 78% 60% Java 8.32 953,620 835 28.37 95% 87% 81% 77% Swift Swift version 5.1.3 (swift-5.1.3-RELEASE) Target: x86_64-unknown-linux-gnu Java openjdk 13 2019-09-17 OpenJDK Runtime Environment (build 13+33) OpenJDK 64-Bit Server VM (build 13+33, mixed mode, sharing) all Swift programs & measurements all Java programs & measurements