OCaml VS Python 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
python 1.py 1162ms 7.5ms 96.8MB 1097ms 47ms pypy 3.11.13
ocaml 1.ml 3087ms 52ms 157.2MB 3003ms 70ms ocaml 5.3.0
python 1.py timeout 0.0ms 41.0MB 4973ms 10ms cpython 3.13.5
python 1.py timeout 0.0ms 40.5MB 4743ms 240ms pyston 3.8.12

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 1.py 94ms 1.5ms 68.2MB 67ms 13ms pypy 3.11.13
ocaml 1.ml 221ms 1.6ms 19.1MB 207ms 0ms ocaml 5.3.0
python 1.py 478ms 3.6ms 11.9MB 457ms 10ms pyston 3.8.12
python 1.py 727ms 3.3ms 12.9MB 717ms 0ms cpython 3.13.5

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
python 1.py 2206ms 28ms 89.1MB 2163ms 33ms pypy 3.11.13
python 5-m.py 2331ms 44ms 66.1MB 3597ms 827ms pypy 3.11.13
python 5-m.py 2434ms 24ms 12.5MB 3547ms 953ms pyston 3.8.12
python 1.py 3030ms 35ms 8.1MB 3013ms 0ms pyston 3.8.12
python 5-m.py 3359ms 19ms 13.8MB 4437ms 910ms cpython 3.13.5
python 1.py 4658ms 45ms 9.0MB 4647ms 0ms cpython 3.13.5

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
python 1.py 279ms 5.1ms 63.3MB 253ms 10ms pypy 3.11.13
python 5-m.py 310ms 3.6ms 12.5MB 397ms 147ms pyston 3.8.12
python 1.py 314ms 1.1ms 8.1MB 300ms 0ms pyston 3.8.12
python 5-m.py 393ms 1.0ms 13.8MB 473ms 127ms cpython 3.13.5
python 5-m.py 449ms 2.7ms 66.2MB 743ms 297ms pypy 3.11.13
python 1.py 486ms 1.2ms 9.0MB 473ms 0ms cpython 3.13.5

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
python 1.py 12ms 0.8ms 7.6MB 0ms 0ms pyston 3.8.12
python 1.py 14ms 1.2ms 8.8MB 10ms 0ms cpython 3.13.5
python 1.py 30ms 0.8ms 52.3MB 10ms 10ms pypy 3.11.13

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 2.py 154ms 2.4ms 58.9MB 130ms 10ms pypy 3.11.13
ocaml 1.ml 173ms 2.7ms 6.4MB 163ms 0ms ocaml 5.3.0
python 1.py 187ms 3.8ms 59.8MB 160ms 10ms pypy 3.11.13
python 1.py 730ms 3.4ms 8.9MB 720ms 0ms pyston 3.8.12
python 2.py 845ms 19ms 8.5MB 833ms 0ms pyston 3.8.12
python 1.py 1136ms 8.0ms 9.5MB 1123ms 0ms cpython 3.13.5
python 2.py 1323ms 19ms 9.3MB 1310ms 0ms cpython 3.13.5

Input: 1000 3000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 2.py 361ms 2.1ms 59.7MB 330ms 10ms pypy 3.11.13
python 1.py 401ms 4.8ms 60.9MB 377ms 13ms pypy 3.11.13
ocaml 1.ml 532ms 18ms 6.6MB 520ms 0ms ocaml 5.3.0
python 1.py 2157ms 16ms 8.9MB 2143ms 0ms pyston 3.8.12
python 2.py 2513ms 23ms 8.5MB 2503ms 0ms pyston 3.8.12
python 1.py 3335ms 53ms 9.5MB 3320ms 0ms cpython 3.13.5
python 2.py 3942ms 29ms 9.3MB 3930ms 0ms cpython 3.13.5

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
python 2.py 109ms 3.1ms 58.1MB 87ms 10ms pypy 3.11.13
python 1.py 124ms 3.2ms 59.4MB 103ms 10ms pypy 3.11.13
python 1.py 361ms 6.0ms 8.5MB 347ms 0ms pyston 3.8.12
python 2.py 388ms 3.0ms 8.1MB 377ms 0ms pyston 3.8.12
python 1.py 534ms 6.3ms 9.3MB 523ms 0ms cpython 3.13.5
python 2.py 638ms 7.1ms 8.9MB 627ms 0ms cpython 3.13.5

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 1077ms 22ms 70.2MB 1037ms 27ms ocaml 5.3.0
ocaml 2.ml 2068ms 35ms 91.8MB 2017ms 37ms ocaml 5.3.0
python 1.py 2184ms 9.5ms 204.9MB 2073ms 97ms pypy 3.11.13
python 1.py timeout 0.0ms 94.1MB 4960ms 27ms cpython 3.13.5
python 1.py timeout 0.0ms 130.4MB 4940ms 47ms pyston 3.8.12

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
ocaml 2.ml 359ms 6.4ms 27.7MB 340ms 7ms ocaml 5.3.0
python 1.py 378ms 3.7ms 105.2MB 320ms 47ms pypy 3.11.13
python 1.py 2994ms 19ms 37.4MB 2970ms 10ms cpython 3.13.5
python 1.py timeout 0.0ms 48.9MB 4943ms 43ms pyston 3.8.12

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 374ms 2.6ms 5.2MB 367ms 0ms ocaml 5.3.0
python 2.py 1348ms 4.2ms 60.6MB 1320ms 10ms pypy 3.11.13
python 1.py 2705ms 69ms 57.8MB 2677ms 13ms pypy 3.11.13
python 1.py timeout 0.0ms 8.9MB 4990ms 0ms cpython 3.13.5
python 2.py timeout 0.0ms 9.0MB 4990ms 0ms cpython 3.13.5
python 1.py timeout 0.0ms 8.3MB 4990ms 0ms pyston 3.8.12
python 2.py timeout 0.0ms 8.1MB 4990ms 0ms pyston 3.8.12

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 40ms 0.1ms 5.2MB 30ms 0ms ocaml 5.3.0
python 2.py 178ms 3.3ms 58.3MB 153ms 10ms pypy 3.11.13
python 1.py 309ms 4.0ms 57.8MB 287ms 10ms pypy 3.11.13
python 1.py 936ms 11ms 8.3MB 927ms 0ms pyston 3.8.12
python 2.py 1312ms 18ms 8.3MB 1300ms 0ms pyston 3.8.12
python 1.py 2893ms 26ms 8.9MB 2883ms 0ms cpython 3.13.5
python 2.py 3043ms 14ms 9.0MB 3030ms 0ms cpython 3.13.5

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
python 1.py 2498ms 18ms 369.9MB 2430ms 53ms pypy 3.11.13
python 2.py 2971ms 13ms 632.9MB 2787ms 167ms pyston 3.8.12
python 1.py 4747ms 19ms 320.5MB 4687ms 47ms pyston 3.8.12
python 1.py timeout 0.0ms 321.4MB 4960ms 23ms cpython 3.13.5
python 2.py timeout 0.0ms 633.8MB 4823ms 163ms cpython 3.13.5
python 2.py timeout 0.0ms 1017.5MB 4707ms 280ms pypy 3.11.13

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
python 1.py 525ms 4.9ms 135.5MB 487ms 20ms pypy 3.11.13
python 2.py 721ms 2.3ms 164.2MB 670ms 33ms pyston 3.8.12
python 1.py 1066ms 26ms 86.0MB 1043ms 10ms pyston 3.8.12
python 2.py 1385ms 12ms 290.8MB 1297ms 73ms pypy 3.11.13
python 2.py 1398ms 5.5ms 165.1MB 1353ms 30ms cpython 3.13.5
python 1.py 2846ms 21ms 87.0MB 2817ms 10ms cpython 3.13.5

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 1.py 2245ms 6.4ms 244.7MB 2187ms 43ms pypy 3.11.13
python 1.py 4731ms 10ms 226.2MB 4540ms 177ms pyston 3.8.12
ocaml 2.ml timeout 0.0ms 462.9MB 4830ms 157ms ocaml 5.3.0
python 1.py timeout 0.0ms 145.6MB 4930ms 57ms cpython 3.13.5

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 1.py 339ms 7.7ms 86.8MB 293ms 30ms pypy 3.11.13
python 1.py 498ms 2.4ms 30.5MB 463ms 17ms pyston 3.8.12
ocaml 2.ml 542ms 2.0ms 57.1MB 510ms 17ms ocaml 5.3.0
python 1.py 613ms 2.2ms 29.7MB 583ms 17ms cpython 3.13.5

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
python 8.py timeout 0.0ms 14.8MB 33ms 10ms cpython 3.13.5
python 8.py timeout 0.0ms 94.7MB 680ms 60ms pypy 3.11.13
python 8.py timeout 0.0ms 14.2MB 33ms 13ms pyston 3.8.12

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
python 8.py timeout 0.0ms 14.5MB 43ms 10ms cpython 3.13.5
python 8.py timeout 0.0ms 97.8MB 1170ms 147ms pypy 3.11.13
python 8.py timeout 0.0ms 13.6MB 57ms 20ms pyston 3.8.12

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
python 8-m.py 2134ms 4.9ms 94.1MB 7090ms 240ms pypy 3.11.13
python 8.py timeout 0.0ms 14.0MB 87ms 17ms cpython 3.13.5
python 8.py timeout 0.0ms 13.2MB 133ms 33ms pyston 3.8.12