Swift VS Java benchmarks

Current benchmark data was generated on Sun Jul 13 2025, full log can be found HERE

CONTRIBUTIONS are WELCOME!

[x86_64][4 cores] AMD EPYC 7763 64-Core Processor (Model 1)

* -m in a file name stands for multi-threading or multi-processing

* -i in a file name stands for direct intrinsics usage. (Usage of simd intrinsics via libraries is not counted)

* -ffi in a file name stands for non-stdlib FFI usage

* (You may find time < time(user) + time(sys) for some non-parallelized programs, the overhead is from GC or JIT compiler, which are allowed to take advantage of multi-cores as that's more close to real-world scenarios.)

binarytrees

Input: 18

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 2.java 455ms 1.0ms 575.9MB 557ms 83ms openjdk 21
java 2-m.java 469ms 4.8ms 641.2MB 673ms 113ms graal/jvm 17.0.8
java 2.java 473ms 8.9ms 642.1MB 573ms 103ms openjdk 23
java 2.java 1191ms 22ms 1054.4MB 577ms 773ms openjdk/zgc 21
swift 1.swift 2692ms 22ms 53.8MB 2657ms 20ms swift 6.1.2

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 2-m.java 125ms 0.6ms 167.1MB 157ms 33ms openjdk 21
java 2.java 129ms 5.0ms 96.0MB 167ms 27ms openjdk 23
java 2-m.java 151ms 3.3ms 227.2MB 220ms 63ms graal/jvm 17.0.8
swift 1.swift 240ms 0.7ms 11.9MB 230ms 0ms swift 6.1.2
java 2.java 305ms 2.0ms 241.5MB 157ms 197ms openjdk/zgc 21

fannkuch-redux

Input: 11

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 901ms 6.8ms 97.1MB 3320ms 40ms graal/jvm 17.0.8
java 1-m.java 983ms 3.0ms 48.4MB 3663ms 17ms openjdk 21
java 1-m.java 987ms 5.3ms 50.2MB 3643ms 20ms openjdk 23
java 1-m.java 1036ms 2.8ms 45.8MB 3383ms 143ms openjdk/zgc 21
swift 1.swift 2463ms 7.5ms 5.5MB 2453ms 0ms swift 6.1.2

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 183ms 8.1ms 48.2MB 497ms 20ms openjdk 21
java 1-m.java 188ms 2.5ms 50.3MB 487ms 23ms openjdk 23
java 1-m.java 205ms 0.3ms 95.9MB 573ms 40ms graal/jvm 17.0.8
swift 1.swift 213ms 2.3ms 5.5MB 200ms 0ms swift 6.1.2
java 1-m.java 299ms 1.9ms 45.9MB 493ms 137ms openjdk/zgc 21

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 3-m.swift 139ms 1.6ms 20.7MB 400ms 3ms swift 6.1.2
java 4.java 448ms 4.7ms 101.5MB 633ms 37ms graal/jvm 17.0.8
java 4.java 458ms 6.9ms 47.4MB 543ms 17ms openjdk 21
java 4.java 464ms 8.8ms 49.1MB 557ms 20ms openjdk 23
java 4.java 566ms 2.0ms 45.1MB 530ms 140ms openjdk/zgc 21

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 3.swift 37ms 0.3ms 14.2MB 30ms 0ms swift 6.1.2
java 4.java 120ms 2.9ms 46.6MB 163ms 13ms openjdk 21
java 4.java 127ms 4.2ms 48.0MB 173ms 17ms openjdk 23
java 4-m.java 131ms 4.7ms 94.1MB 183ms 37ms graal/jvm 17.0.8
java 4.java 242ms 2.2ms 43.9MB 163ms 137ms openjdk/zgc 21

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 1.swift 2.4ms 0.1ms 5.6MB 0ms 0ms swift 6.1.2
java 1.java 62ms 2.2ms 52.9MB 66ms 18ms graal/jvm 17.0.8
java 1.java 67ms 7.0ms 43.8MB 74ms 18ms openjdk 21
java 1.java 71ms 5.3ms 44.7MB 74ms 16ms openjdk 23
java 1.java 193ms 7.2ms 42.8MB 82ms 136ms openjdk/zgc 21

knucleotide

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 3-m.java 1030ms 58ms 127.6MB 3553ms 33ms openjdk 21
java 3-m.java 1084ms 15ms 158.2MB 3720ms 43ms openjdk 23
java 3-m.java 1100ms 49ms 179.0MB 3693ms 73ms graal/jvm 17.0.8
swift 2-m.swift 1361ms 16ms 74.3MB 4960ms 37ms swift 6.1.2
java 3-m.java 1449ms 55ms 179.3MB 4600ms 200ms openjdk/zgc 21

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 2-m.swift 251ms 2.0ms 60.0MB 663ms 30ms swift 6.1.2
java 3-m.java 338ms 53ms 96.3MB 993ms 50ms openjdk 21
java 3-m.java 341ms 21ms 136.0MB 907ms 60ms graal/jvm 17.0.8
java 3-m.java 345ms 34ms 88.9MB 1023ms 40ms openjdk 23
java 3-m.java 426ms 6.6ms 98.2MB 890ms 170ms openjdk/zgc 21

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 7.swift 346ms 2.1ms 9.9MB 337ms 0ms swift 6.1.2
java 1.java 442ms 1.0ms 45.1MB 480ms 17ms openjdk 21
java 1.java 444ms 3.9ms 48.3MB 480ms 23ms openjdk 23
java 1.java 454ms 0.5ms 81.1MB 490ms 30ms graal/jvm 17.0.8
java 1.java 563ms 6.0ms 44.7MB 483ms 133ms openjdk/zgc 21
java 2.java 1235ms 3.8ms 571.4MB 1363ms 87ms openjdk 21
java 2.java 1310ms 91ms 794.4MB 1433ms 93ms openjdk 23
java 2.java 3270ms 60ms 2461.0MB 1670ms 1817ms openjdk/zgc 21

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 7.swift 39ms 0.9ms 9.9MB 30ms 0ms swift 6.1.2
java 1.java 116ms 4.0ms 45.4MB 143ms 23ms openjdk 21
java 1.java 119ms 2.3ms 81.5MB 150ms 27ms graal/jvm 17.0.8
java 1.java 120ms 2.0ms 47.9MB 157ms 13ms openjdk 23
java 1.java 240ms 5.7ms 44.7MB 153ms 140ms openjdk/zgc 21
java 2-m.java 294ms 9.4ms 366.4MB 437ms 50ms openjdk 21
java 2-m.java 317ms 4.3ms 397.4MB 450ms 67ms openjdk 23
java 2.java 674ms 5.7ms 533.2MB 460ms 400ms openjdk/zgc 21

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1.java 3212ms 15ms 444.6MB 3627ms 110ms graal/jvm 17.0.8
java 1.java 3669ms 54ms 426.1MB 4610ms 110ms openjdk 21
java 1.java 3752ms 19ms 501.5MB 4603ms 120ms openjdk 23
java 1.java timeout 0.0ms 1758.6MB 4670ms 1183ms openjdk/zgc 21
swift 1.swift timeout 0.0ms 7.3MB 4927ms 60ms swift 6.1.2

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1.java 896ms 13ms 444.3MB 1243ms 87ms graal/jvm 17.0.8
java 1-m.java 1001ms 28ms 353.6MB 1797ms 90ms openjdk 21
java 1-m.java 1015ms 31ms 423.3MB 1787ms 93ms openjdk 23
swift 1.swift 1865ms 11ms 7.0MB 1853ms 0ms swift 6.1.2
java 1.java 2003ms 34ms 1358.4MB 1703ms 1060ms openjdk/zgc 21