Kotlin 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
kotlin 1.kt 502ms 0.9ms 575.9MB 597ms 100ms kotlin/jvm 21
java 2.java 1191ms 22ms 1054.4MB 577ms 773ms openjdk/zgc 21
kotlin 1.kt 4076ms 141ms 134.1MB 4270ms 63ms kotlin/native 2.1.20

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 122ms 1.3ms 159.4MB 143ms 30ms kotlin/jvm 21
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
kotlin 1.kt 232ms 38ms 17.6MB 243ms 3ms kotlin/native 2.1.20
java 2.java 305ms 2.0ms 241.5MB 157ms 197ms openjdk/zgc 21

coro-prime-sieve

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 1827ms 163ms 237.7MB 6800ms 107ms kotlin/jvm 21
kotlin 1.kt 2186ms 6.6ms 220.6MB 2997ms 70ms kotlin/jvm 21
java 1-m.java 2305ms 190ms 264.5MB 8783ms 140ms openjdk 21
java 1-m.java 2419ms 254ms 243.1MB 9207ms 137ms openjdk 23
java 1-m.java 2938ms 109ms 1226.1MB 9570ms 1070ms openjdk/zgc 21
kotlin 2-m.kt 4215ms 20ms 21.1MB 14100ms 557ms kotlin/native 2.1.20
kotlin 1.kt timeout 0.0ms 17.3MB 5513ms 27ms kotlin/native 2.1.20

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 247ms 1.2ms 21.4MB 833ms 37ms kotlin/native 2.1.20
kotlin 1.kt 402ms 30ms 17.5MB 410ms 7ms kotlin/native 2.1.20
java 1-m.java 464ms 5.9ms 96.8MB 1527ms 67ms openjdk 23
java 1-m.java 473ms 16ms 121.6MB 1597ms 57ms openjdk 21
kotlin 1-m.kt 479ms 3.4ms 75.2MB 1080ms 47ms kotlin/jvm 21
java 1-m.java 654ms 16ms 213.4MB 1803ms 237ms openjdk/zgc 21
kotlin 2-m.kt 877ms 85ms 99.4MB 3073ms 70ms kotlin/jvm 21

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 2.2ms 0.1ms 3.0MB 0ms 0ms kotlin/native 2.1.20
java 1.java 62ms 2.2ms 52.9MB 66ms 18ms graal/jvm 17.0.8
kotlin 1.kt 62ms 0.6ms 47.7MB 74ms 18ms kotlin/jvm 21
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

http-server

Input: 3000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 811ms 1405ms 357.9MB 10610ms 1887ms kotlin/jvm 21
kotlin 1.kt timeout 0.0ms 369.3MB 16190ms 2853ms kotlin/jvm 21

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 2031ms 194ms 211.9MB 5813ms 603ms kotlin/jvm 21
kotlin 2-m.kt 2032ms 138ms 242.0MB 5440ms 617ms kotlin/jvm 21

json-serde

Input: sample 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 732ms 78ms 173.7MB 1963ms 80ms kotlin/jvm 21

Input: canada 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 1722ms 19ms 650.0MB 4150ms 150ms kotlin/jvm 21

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2.kt 166ms 1.3ms 12.4MB 170ms 0ms kotlin/native 2.1.20
kotlin 1-m.kt 192ms 1.4ms 95.1MB 327ms 27ms kotlin/jvm 21
kotlin 2-m.kt 201ms 1.3ms 101.4MB 460ms 30ms kotlin/jvm 21
kotlin 1.kt 355ms 2.2ms 12.5MB 360ms 0ms kotlin/native 2.1.20

Input: 1000 3000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 315ms 3.2ms 213.2MB 557ms 47ms kotlin/jvm 21
kotlin 1.kt 344ms 7.7ms 202.9MB 473ms 37ms kotlin/jvm 21
kotlin 2.kt 477ms 5.7ms 12.4MB 507ms 0ms kotlin/native 2.1.20
kotlin 1.kt 1032ms 3.9ms 12.5MB 1060ms 0ms kotlin/native 2.1.20

Input: 100 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2.kt 94ms 0.6ms 12.8MB 87ms 0ms kotlin/native 2.1.20
kotlin 1.kt 120ms 1.0ms 12.8MB 120ms 0ms kotlin/native 2.1.20
kotlin 1-m.kt 153ms 2.7ms 91.1MB 290ms 30ms kotlin/jvm 21
kotlin 2-m.kt 167ms 13ms 96.2MB 343ms 33ms kotlin/jvm 21

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 387ms 9.9ms 680.6MB 443ms 93ms kotlin/jvm 21
java 1.java 401ms 5.9ms 544.3MB 500ms 87ms openjdk 23
java 1.java 403ms 2.1ms 680.0MB 480ms 87ms openjdk 21
java 1-m.java 444ms 62ms 669.4MB 667ms 113ms graal/jvm 17.0.8
java 1.java 1021ms 2.8ms 934.5MB 470ms 697ms openjdk/zgc 21
kotlin 1.kt 1895ms 31ms 90.1MB 1967ms 43ms kotlin/native 2.1.20

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 155ms 0.4ms 207.1MB 213ms 40ms kotlin/jvm 21
java 1-m.java 164ms 3.1ms 158.5MB 237ms 43ms openjdk 23
java 1-m.java 170ms 10ms 206.6MB 237ms 47ms openjdk 21
java 1-m.java 221ms 7.1ms 253.9MB 363ms 63ms graal/jvm 17.0.8
kotlin 1.kt 267ms 13ms 25.5MB 270ms 13ms kotlin/native 2.1.20
java 1.java 411ms 7.8ms 341.9MB 223ms 267ms openjdk/zgc 21

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1n.kt 354ms 5.0ms 3.6MB 343ms 0ms kotlin/native 2.1.20
java 1.java 442ms 1.0ms 45.1MB 480ms 17ms openjdk 21
kotlin 1.kt 443ms 0.3ms 49.2MB 487ms 13ms kotlin/jvm 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
kotlin 1n.kt 39ms 1.6ms 3.6MB 30ms 0ms kotlin/native 2.1.20
java 1.java 116ms 4.0ms 45.4MB 143ms 23ms openjdk 21
kotlin 1-m.kt 119ms 1.7ms 49.5MB 170ms 13ms kotlin/jvm 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
kotlin 1.kt 3757ms 42ms 354.4MB 4560ms 113ms kotlin/jvm 21
java 1.java timeout 0.0ms 1758.6MB 4670ms 1183ms openjdk/zgc 21
kotlin 1n.kt timeout 0.0ms 26.6MB 3957ms 1507ms kotlin/native 2.1.20
kotlin 2n.kt timeout 0.0ms 30.6MB 5110ms 133ms kotlin/native 2.1.20

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
kotlin 1-m.kt 990ms 32ms 353.0MB 1737ms 93ms kotlin/jvm 21
java 1-m.java 1001ms 28ms 353.6MB 1797ms 90ms openjdk 21
java 1-m.java 1015ms 31ms 423.3MB 1787ms 93ms openjdk 23
java 1.java 2003ms 34ms 1358.4MB 1703ms 1060ms openjdk/zgc 21
kotlin 1n.kt timeout 0.0ms 26.3MB 3987ms 1517ms kotlin/native 2.1.20
kotlin 2n.kt timeout 0.0ms 30.9MB 5117ms 123ms kotlin/native 2.1.20

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 3.java timeout 0.0ms 407.7MB 5397ms 93ms graal/jvm 17.0.8
java 3.java timeout 0.0ms 302.1MB 5333ms 53ms openjdk 21
java 3.java timeout 0.0ms 304.8MB 5320ms 67ms openjdk 23
java 3.java timeout 0.0ms 471.1MB 4957ms 303ms openjdk/zgc 21
kotlin 1.kt timeout 0.0ms 173.5MB 5407ms 40ms kotlin/jvm 21
kotlin 1n.kt timeout 0.0ms 226.8MB 5060ms 130ms kotlin/native 2.1.20

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 3-m.java 782ms 10ms 175.4MB 1160ms 47ms graal/jvm 17.0.8
java 3-m.java 806ms 18ms 130.9MB 1183ms 33ms openjdk 21
java 3-m.java 814ms 8.2ms 132.4MB 1230ms 30ms openjdk 23
kotlin 1-m.kt 830ms 6.8ms 134.5MB 1273ms 37ms kotlin/jvm 21
java 3.java 963ms 9.6ms 133.9MB 1133ms 177ms openjdk/zgc 21
kotlin 1n.kt 3212ms 16ms 51.0MB 3280ms 80ms kotlin/native 2.1.20

secp256k1

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 3105ms 26ms 233.3MB 3997ms 67ms kotlin/jvm 21

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 1013ms 41ms 232.1MB 1923ms 67ms kotlin/jvm 21