OCaml VS Nim benchmarks

Current benchmark data was generated on Mon Jun 23 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
nim 2.nim 825ms 37ms 34.9MB 807ms 7ms nim 2.2.4
nim 2.nim 999ms 22ms 34.7MB 980ms 7ms nim/clang 2.2.4
ocaml 1.ml 3028ms 44ms 157.2MB 2940ms 73ms ocaml 5.3.0

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 77ms 1.9ms 5.5MB 67ms 0ms nim 2.2.4
nim 2.nim 93ms 2.8ms 5.8MB 83ms 0ms nim/clang 2.2.4
ocaml 1.ml 214ms 0.9ms 19.1MB 200ms 0ms ocaml 5.3.0

fannkuch-redux

Input: 11

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 2914ms 16ms 4.9MB 2907ms 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 3.3ms 4.9MB 237ms 0ms ocaml 5.3.0

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 188ms 2.2ms 1.5MB 180ms 0ms nim 2.2.4
nim 2.nim 240ms 0.1ms 1.8MB 230ms 0ms nim/clang 2.2.4
ocaml 6.ml 347ms 1.7ms 24.8MB 337ms 0ms ocaml 5.3.0
nim 1.nim 542ms 2.9ms 1.9MB 450ms 80ms nim/clang 2.2.4
nim 1.nim 561ms 3.3ms 1.5MB 470ms 77ms nim 2.2.4

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 21ms 0.1ms 1.5MB 10ms 0ms nim 2.2.4
nim 2.nim 27ms 1.0ms 1.8MB 20ms 0ms nim/clang 2.2.4
ocaml 6.ml 39ms 0.5ms 7.5MB 30ms 0ms ocaml 5.3.0
nim 1.nim 57ms 0.5ms 1.8MB 37ms 3ms nim/clang 2.2.4
nim 1.nim 59ms 0.6ms 1.5MB 40ms 7ms nim 2.2.4

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 1.0ms 0.0ms 1.6MB 0ms 0ms nim 2.2.4
nim 1.nim 1.1ms 0.0ms 1.9MB 0ms 0ms nim/clang 2.2.4
ocaml 1.ml 1.8ms 0.2ms 5.0MB 0ms 0ms ocaml 5.3.0

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 113ms 2.8ms 1.8MB 107ms 0ms nim/clang 2.2.4
nim 2.nim 116ms 1.5ms 1.4MB 110ms 0ms nim 2.2.4
ocaml 1.ml 190ms 0.6ms 6.4MB 180ms 0ms ocaml 5.3.0
nim 1.nim timeout 0.0ms 1.3MB 4990ms 0ms nim 2.2.4
nim 1.nim timeout 0.0ms 1.5MB 4990ms 0ms nim/clang 2.2.4

Input: 1000 3000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 328ms 6.2ms 1.6MB 317ms 0ms nim/clang 2.2.4
nim 2.nim 336ms 4.0ms 1.4MB 330ms 0ms nim 2.2.4
ocaml 1.ml 518ms 3.2ms 6.6MB 510ms 0ms ocaml 5.3.0
nim 1.nim timeout 0.0ms 1.3MB 4990ms 0ms nim 2.2.4
nim 1.nim timeout 0.0ms 1.5MB 4990ms 0ms nim/clang 2.2.4

Input: 100 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 48ms 0.0ms 1.8MB 40ms 0ms nim/clang 2.2.4
nim 2.nim 50ms 0.4ms 1.3MB 40ms 0ms nim 2.2.4
ocaml 1.ml 77ms 1.4ms 5.9MB 70ms 0ms ocaml 5.3.0
nim 1.nim 478ms 6.6ms 1.5MB 470ms 0ms nim/clang 2.2.4
nim 1.nim 483ms 14ms 1.3MB 477ms 0ms nim 2.2.4

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 568ms 19ms 34.9MB 550ms 3ms nim 2.2.4
nim 1.nim 633ms 12ms 34.2MB 617ms 3ms nim/clang 2.2.4
ocaml 1.ml 1094ms 11ms 70.2MB 1047ms 30ms ocaml 5.3.0
ocaml 2.ml 2066ms 16ms 91.8MB 2013ms 33ms ocaml 5.3.0

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 119ms 2.4ms 9.6MB 107ms 0ms nim 2.2.4
nim 1.nim 138ms 2.2ms 9.9MB 127ms 0ms nim/clang 2.2.4
ocaml 1.ml 147ms 4.1ms 21.7MB 130ms 7ms ocaml 5.3.0
ocaml 2.ml 367ms 7.6ms 27.7MB 343ms 7ms ocaml 5.3.0

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 321ms 2.4ms 1.8MB 310ms 0ms nim 2.2.4
nim 2.nim 344ms 1.2ms 1.9MB 330ms 0ms nim/clang 2.2.4
ocaml 1.ml 373ms 1.9ms 5.2MB 360ms 0ms ocaml 5.3.0

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 34ms 0.6ms 1.8MB 30ms 0ms nim 2.2.4
nim 2.nim 38ms 1.4ms 2.0MB 30ms 0ms nim/clang 2.2.4
ocaml 1.ml 41ms 1.4ms 5.2MB 30ms 0ms ocaml 5.3.0

nsieve

Input: 12

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 306ms 36ms 41.5MB 297ms 0ms nim 2.2.4
nim 1.nim 334ms 13ms 41.8MB 323ms 0ms nim/clang 2.2.4
ocaml 1.ml 957ms 3.4ms 550.3MB 900ms 43ms ocaml 5.3.0
ocaml 2.ml 1886ms 14ms 18.9MB 1873ms 0ms ocaml 5.3.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 51ms 1.1ms 11.5MB 40ms 0ms nim 2.2.4
nim 1.nim 67ms 7.6ms 11.8MB 60ms 0ms nim/clang 2.2.4
ocaml 1.ml 191ms 3.0ms 141.6MB 170ms 10ms ocaml 5.3.0
ocaml 2.ml 471ms 4.3ms 9.1MB 460ms 0ms ocaml 5.3.0

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 1646ms 3.9ms 152.4MB 1610ms 23ms nim/clang 2.2.4
nim 1.nim 1674ms 7.4ms 151.5MB 1640ms 20ms nim 2.2.4
ocaml 2.ml timeout 0.0ms 462.9MB 4830ms 153ms ocaml 5.3.0

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 174ms 3.1ms 17.6MB 160ms 0ms nim/clang 2.2.4
nim 1.nim 178ms 1.7ms 17.4MB 160ms 0ms nim 2.2.4
ocaml 2.ml 549ms 4.5ms 57.1MB 513ms 23ms ocaml 5.3.0

spectral-norm

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 3589ms 1.4ms 2.0MB 3580ms 0ms nim/clang 2.2.4
nim 1.nim 3601ms 3.5ms 1.4MB 3593ms 0ms nim 2.2.4
ocaml 2.ml 4582ms 24ms 6.4MB 4570ms 0ms ocaml 5.3.0

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 899ms 0.7ms 1.5MB 890ms 0ms nim/clang 2.2.4
nim 1.nim 903ms 1.2ms 1.3MB 893ms 0ms nim 2.2.4
ocaml 2.ml 1159ms 5.5ms 6.1MB 1150ms 0ms ocaml 5.3.0

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 227ms 0.4ms 1.5MB 220ms 0ms nim/clang 2.2.4
nim 1.nim 228ms 1.8ms 1.3MB 220ms 0ms nim 2.2.4
ocaml 2.ml 294ms 4.6ms 5.2MB 283ms 0ms ocaml 5.3.0