Results for 38 of 40 languages from this run on actest1.

Unavailable in this run: Hack, Lisp. Follow the run link for failure details.

Kotlin VS Java benchmarks

Current benchmark data was generated on Sun Sep 27 2026, full log can be found HERE

CONTRIBUTIONS are WELCOME!

[x86_64][4 cores] Intel(R) Core(TM) i7-3687U CPU @ 2.10GHz (Model 58)

* -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 782ms 124ms 569.1MB 957ms 133ms openjdk 21.0.12
kotlin 1.kt 794ms 80ms 581.9MB 1017ms 130ms kotlin/jvm 21.0.12
java 2.java 1276ms 44ms 1086.4MB 900ms 603ms openjdk/zgc 21.0.12

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 188ms 30ms 159.7MB 233ms 30ms kotlin/jvm 21.0.12
java 2.java 192ms 18ms 167.6MB 260ms 27ms openjdk 21.0.12
java 2.java 378ms 84ms 239.8MB 267ms 200ms openjdk/zgc 21.0.12

coro-prime-sieve

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 2953ms 188ms 213.9MB 11130ms 147ms openjdk 21.0.12
kotlin 2-m.kt 3342ms 283ms 229.6MB 12590ms 123ms kotlin/jvm 21.0.12
kotlin 1.kt 3615ms 290ms 219.6MB 4723ms 107ms kotlin/jvm 21.0.12
java 1-m.java 3742ms 52ms 618.0MB 13450ms 670ms openjdk/zgc 21.0.12

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 545ms 57ms 74.1MB 1767ms 40ms openjdk 21.0.12
java 1-m.java 671ms 12ms 150.9MB 1950ms 203ms openjdk/zgc 21.0.12
kotlin 1-m.kt 738ms 7.2ms 77.4MB 1727ms 47ms kotlin/jvm 21.0.12
kotlin 2-m.kt 1625ms 206ms 97.5MB 5807ms 100ms kotlin/jvm 21.0.12

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 87ms 4.3ms 46.2MB 136ms 12ms kotlin/jvm 21.0.12
java 1.java 93ms 5.3ms 44.3MB 116ms 12ms openjdk 21.0.12
java 1.java 165ms 3.2ms 42.8MB 128ms 88ms openjdk/zgc 21.0.12

http-server

Input: 3000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 9841ms 283ms 341.7MB 32387ms 3343ms kotlin/jvm 21.0.12
kotlin 1-m.kt 11376ms 242ms 433.1MB 37790ms 4520ms kotlin/jvm 21.0.12

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 3791ms 276ms 249.0MB 11797ms 810ms kotlin/jvm 21.0.12
kotlin 1-m.kt 3917ms 180ms 275.4MB 12153ms 857ms kotlin/jvm 21.0.12

json-serde

Input: sample 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 1371ms 105ms 176.1MB 3830ms 140ms kotlin/jvm 21.0.12

Input: canada 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 3079ms 117ms 749.4MB 7240ms 250ms kotlin/jvm 21.0.12

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 284ms 4.7ms 95.4MB 503ms 33ms kotlin/jvm 21.0.12
kotlin 2-m.kt 389ms 13ms 99.5MB 863ms 27ms kotlin/jvm 21.0.12

Input: 1000 3000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 482ms 4.8ms 201.4MB 717ms 47ms kotlin/jvm 21.0.12
kotlin 2-m.kt 543ms 5.7ms 209.8MB 993ms 67ms kotlin/jvm 21.0.12

Input: 100 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 255ms 1.9ms 91.1MB 500ms 37ms kotlin/jvm 21.0.12
kotlin 2-m.kt 302ms 15ms 95.4MB 693ms 23ms kotlin/jvm 21.0.12

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1.java 639ms 19ms 672.5MB 787ms 113ms openjdk 21.0.12
kotlin 1.kt 641ms 8.2ms 676.7MB 820ms 93ms kotlin/jvm 21.0.12
java 1.java 1091ms 23ms 952.0MB 723ms 573ms openjdk/zgc 21.0.12

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 244ms 6.2ms 203.4MB 380ms 43ms openjdk 21.0.12
kotlin 1-m.kt 250ms 11ms 205.0MB 363ms 67ms kotlin/jvm 21.0.12
java 1.java 494ms 111ms 341.8MB 367ms 237ms openjdk/zgc 21.0.12

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1.java 836ms 7.8ms 45.3MB 903ms 20ms openjdk 21.0.12
kotlin 1.kt 884ms 6.3ms 49.9MB 980ms 17ms kotlin/jvm 21.0.12
java 1.java 948ms 8.1ms 42.6MB 943ms 97ms openjdk/zgc 21.0.12
java 2.java 2391ms 105ms 668.4MB 2600ms 133ms openjdk 21.0.12
java 2.java 4242ms 39ms 2140.1MB 3463ms 1093ms openjdk/zgc 21.0.12

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1-m.java 192ms 4.7ms 45.4MB 267ms 23ms openjdk 21.0.12
kotlin 1-m.kt 208ms 14ms 49.7MB 297ms 17ms kotlin/jvm 21.0.12
java 1.java 284ms 11ms 45.1MB 267ms 110ms openjdk/zgc 21.0.12
java 2-m.java 470ms 6.5ms 319.0MB 713ms 53ms openjdk 21.0.12
java 2.java 889ms 1.9ms 558.5MB 850ms 327ms openjdk/zgc 21.0.12

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 1.java 5357ms 89ms 417.2MB 6753ms 143ms openjdk 21.0.12
kotlin 1.kt 5427ms 177ms 419.0MB 6873ms 170ms kotlin/jvm 21.0.12
java 1.java 6538ms 393ms 2905.5MB 6313ms 1513ms openjdk/zgc 21.0.12

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 1629ms 66ms 362.2MB 3007ms 117ms kotlin/jvm 21.0.12
java 1-m.java 1639ms 92ms 421.6MB 2920ms 107ms openjdk 21.0.12
java 1-m.java 2264ms 50ms 1392.4MB 2540ms 883ms openjdk/zgc 21.0.12

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 3.java 8627ms 72ms 563.4MB 9447ms 103ms openjdk 21.0.12
kotlin 1.kt 8673ms 241ms 178.9MB 9617ms 70ms kotlin/jvm 21.0.12
java 3.java 9355ms 276ms 737.5MB 9407ms 507ms openjdk/zgc 21.0.12

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
java 3-m.java 1230ms 47ms 131.7MB 1947ms 43ms openjdk 21.0.12
kotlin 1-m.kt 1293ms 57ms 133.7MB 2110ms 47ms kotlin/jvm 21.0.12
java 3.java 1312ms 29ms 134.7MB 1800ms 130ms openjdk/zgc 21.0.12

secp256k1

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 5266ms 83ms 228.7MB 6800ms 87ms kotlin/jvm 21.0.12

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 1750ms 44ms 260.1MB 2960ms 50ms kotlin/jvm 21.0.12