OCaml VS Kotlin 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
kotlin 1.kt 502ms 0.9ms 575.9MB 597ms 100ms kotlin/jvm 21
ocaml 1.ml 3087ms 52ms 157.2MB 3003ms 70ms ocaml 5.3.0
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
ocaml 1.ml 221ms 1.6ms 19.1MB 207ms 0ms ocaml 5.3.0
kotlin 1.kt 232ms 38ms 17.6MB 243ms 3ms kotlin/native 2.1.20

fannkuch-redux

Input: 11

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 2909ms 4.1ms 4.9MB 2903ms 0ms ocaml 5.3.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 245ms 0.8ms 5.2MB 237ms 0ms ocaml 5.3.0

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 6.ml 346ms 1.9ms 24.8MB 330ms 0ms ocaml 5.3.0

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 6.ml 39ms 0.7ms 7.4MB 30ms 0ms ocaml 5.3.0

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 1.8ms 0.1ms 5.0MB 0ms 0ms ocaml 5.3.0
kotlin 1.kt 2.2ms 0.1ms 3.0MB 0ms 0ms kotlin/native 2.1.20
kotlin 1.kt 62ms 0.6ms 47.7MB 74ms 18ms 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
ocaml 1.ml 173ms 2.7ms 6.4MB 163ms 0ms ocaml 5.3.0
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
ocaml 1.ml 532ms 18ms 6.6MB 520ms 0ms ocaml 5.3.0
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
ocaml 1.ml 78ms 0.4ms 6.2MB 70ms 0ms ocaml 5.3.0
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
ocaml 1.ml 1077ms 22ms 70.2MB 1037ms 27ms ocaml 5.3.0
kotlin 1.kt 1895ms 31ms 90.1MB 1967ms 43ms kotlin/native 2.1.20
ocaml 2.ml 2068ms 35ms 91.8MB 2017ms 37ms ocaml 5.3.0

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 144ms 1.4ms 21.7MB 127ms 3ms ocaml 5.3.0
kotlin 1-m.kt 155ms 0.4ms 207.1MB 213ms 40ms kotlin/jvm 21
kotlin 1.kt 267ms 13ms 25.5MB 270ms 13ms kotlin/native 2.1.20
ocaml 2.ml 359ms 6.4ms 27.7MB 340ms 7ms ocaml 5.3.0

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
ocaml 1.ml 374ms 2.6ms 5.2MB 367ms 0ms ocaml 5.3.0
kotlin 1.kt 443ms 0.3ms 49.2MB 487ms 13ms kotlin/jvm 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
ocaml 1.ml 40ms 0.1ms 5.2MB 30ms 0ms ocaml 5.3.0
kotlin 1-m.kt 119ms 1.7ms 49.5MB 170ms 13ms kotlin/jvm 21

nsieve

Input: 12

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 945ms 11ms 547.9MB 883ms 47ms ocaml 5.3.0
ocaml 2.ml 1884ms 7.1ms 17.2MB 1870ms 0ms ocaml 5.3.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 178ms 0.8ms 142.3MB 153ms 10ms ocaml 5.3.0
ocaml 2.ml 464ms 1.5ms 9.3MB 453ms 0ms ocaml 5.3.0

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
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
ocaml 2.ml timeout 0.0ms 462.9MB 4830ms 157ms ocaml 5.3.0

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 542ms 2.0ms 57.1MB 510ms 17ms ocaml 5.3.0
kotlin 1-m.kt 830ms 6.8ms 134.5MB 1273ms 37ms kotlin/jvm 21
kotlin 1n.kt 3212ms 16ms 51.0MB 3280ms 80ms kotlin/native 2.1.20

spectral-norm

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 4558ms 6.5ms 6.3MB 4543ms 0ms ocaml 5.3.0

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 1146ms 5.3ms 6.1MB 1137ms 0ms ocaml 5.3.0

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 296ms 9.1ms 5.2MB 287ms 0ms ocaml 5.3.0