OCaml VS Python benchmarks

Current benchmark data was generated on Tue Jul 01 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 1158ms 1.0ms 96.1MB 1093ms 53ms pypy 3.10.16
ocaml 1.ml 3177ms 13ms 157.2MB 3097ms 63ms ocaml 5.3.0
python 1.py timeout 0.0ms 41.0MB 4963ms 17ms cpython 3.13.5
python 1.py timeout 0.0ms 40.5MB 4753ms 233ms pyston 3.8.12

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 1.py 93ms 0.2ms 68.8MB 67ms 17ms pypy 3.10.16
ocaml 1.ml 234ms 3.5ms 19.2MB 217ms 0ms ocaml 5.3.0
python 1.py 477ms 1.2ms 11.9MB 453ms 13ms pyston 3.8.12
python 1.py 718ms 3.5ms 13.0MB 707ms 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 2910ms 4.7ms 4.9MB 2900ms 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 1.0ms 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
ocaml 6.ml 348ms 0.3ms 24.8MB 337ms 0ms ocaml 5.3.0
python 1.py 1857ms 11ms 88.9MB 1810ms 30ms pypy 3.10.16
python 5-m.py 2292ms 35ms 65.6MB 3537ms 850ms pypy 3.10.16
python 5-m.py 2462ms 20ms 12.5MB 3543ms 983ms pyston 3.8.12
python 1.py 3024ms 23ms 8.1MB 3007ms 0ms pyston 3.8.12
python 5-m.py 3410ms 32ms 13.8MB 4480ms 947ms cpython 3.13.5
python 1.py 4667ms 43ms 9.0MB 4653ms 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 0.9ms 7.6MB 30ms 0ms ocaml 5.3.0
python 1.py 250ms 0.9ms 63.4MB 220ms 10ms pypy 3.10.16
python 5-m.py 315ms 11ms 12.5MB 390ms 157ms pyston 3.8.12
python 1.py 315ms 4.7ms 8.1MB 303ms 0ms pyston 3.8.12
python 5-m.py 407ms 7.3ms 13.8MB 483ms 143ms cpython 3.13.5
python 5-m.py 446ms 3.8ms 65.6MB 753ms 297ms pypy 3.10.16
python 1.py 484ms 2.4ms 9.0MB 470ms 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 0.2ms 5.1MB 0ms 0ms ocaml 5.3.0
python 1.py 12ms 0.7ms 7.6MB 10ms 0ms pyston 3.8.12
python 1.py 15ms 1.2ms 8.8MB 10ms 0ms cpython 3.13.5
python 1.py 30ms 0.9ms 51.7MB 6ms 12ms pypy 3.10.16

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 2.py 147ms 1.1ms 58.3MB 120ms 10ms pypy 3.10.16
python 1.py 178ms 1.7ms 59.4MB 153ms 10ms pypy 3.10.16
ocaml 1.ml 180ms 10ms 6.4MB 170ms 0ms ocaml 5.3.0
python 1.py 730ms 8.0ms 8.9MB 720ms 0ms pyston 3.8.12
python 2.py 850ms 11ms 8.5MB 840ms 0ms pyston 3.8.12
python 1.py 1141ms 7.1ms 9.5MB 1133ms 0ms cpython 3.13.5
python 2.py 1304ms 8.0ms 9.3MB 1290ms 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 339ms 1.2ms 60.5MB 317ms 10ms pypy 3.10.16
python 1.py 380ms 4.2ms 60.3MB 357ms 10ms pypy 3.10.16
ocaml 1.ml 537ms 22ms 6.6MB 527ms 0ms ocaml 5.3.0
python 1.py 2148ms 10ms 8.9MB 2137ms 0ms pyston 3.8.12
python 2.py 2496ms 44ms 8.5MB 2483ms 0ms pyston 3.8.12
python 1.py 3362ms 46ms 9.5MB 3350ms 0ms cpython 3.13.5
python 2.py 3908ms 18ms 9.3MB 3897ms 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 77ms 0.7ms 5.9MB 70ms 0ms ocaml 5.3.0
python 2.py 107ms 3.6ms 58.2MB 80ms 10ms pypy 3.10.16
python 1.py 122ms 3.9ms 58.8MB 97ms 10ms pypy 3.10.16
python 1.py 355ms 5.9ms 8.5MB 343ms 0ms pyston 3.8.12
python 2.py 385ms 2.9ms 8.1MB 373ms 0ms pyston 3.8.12
python 1.py 537ms 11ms 9.3MB 527ms 0ms cpython 3.13.5
python 2.py 628ms 9.6ms 8.9MB 617ms 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 1078ms 7.3ms 70.2MB 1040ms 27ms ocaml 5.3.0
ocaml 2.ml 2068ms 16ms 91.7MB 2013ms 40ms ocaml 5.3.0
python 1.py 2196ms 9.7ms 202.5MB 2077ms 100ms pypy 3.10.16
python 1.py timeout 0.0ms 94.1MB 4960ms 27ms cpython 3.13.5
python 1.py timeout 0.0ms 130.3MB 4930ms 57ms pyston 3.8.12

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 145ms 3.7ms 21.7MB 130ms 0ms ocaml 5.3.0
ocaml 2.ml 361ms 9.3ms 27.7MB 340ms 7ms ocaml 5.3.0
python 1.py 385ms 4.5ms 104.7MB 323ms 50ms pypy 3.10.16
python 1.py 3347ms 32ms 37.4MB 3317ms 13ms cpython 3.13.5
python 1.py timeout 0.0ms 48.9MB 4953ms 37ms pyston 3.8.12

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 375ms 3.2ms 5.3MB 363ms 0ms ocaml 5.3.0
python 2.py 1358ms 8.1ms 58.1MB 1333ms 10ms pypy 3.10.16
python 1.py 2644ms 7.4ms 57.0MB 2620ms 10ms pypy 3.10.16
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 41ms 1.9ms 5.2MB 33ms 0ms ocaml 5.3.0
python 2.py 182ms 1.2ms 57.9MB 160ms 10ms pypy 3.10.16
python 1.py 304ms 1.2ms 57.1MB 280ms 10ms pypy 3.10.16
python 1.py 921ms 6.9ms 8.4MB 910ms 0ms pyston 3.8.12
python 2.py 1314ms 5.3ms 8.3MB 1300ms 0ms pyston 3.8.12
python 2.py 2943ms 21ms 9.0MB 2930ms 0ms cpython 3.13.5
python 1.py 3003ms 91ms 9.0MB 2990ms 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 949ms 8.7ms 543.2MB 887ms 47ms ocaml 5.3.0
ocaml 2.ml 1888ms 14ms 17.7MB 1877ms 0ms ocaml 5.3.0
python 1.py 2563ms 130ms 369.7MB 2490ms 57ms pypy 3.10.16
python 2.py 2996ms 31ms 632.9MB 2817ms 167ms pyston 3.8.12
python 1.py 4717ms 60ms 320.4MB 4660ms 40ms pyston 3.8.12
python 1.py timeout 0.0ms 321.4MB 4967ms 23ms cpython 3.13.5
python 2.py timeout 0.0ms 633.8MB 4823ms 157ms cpython 3.13.5
python 2.py timeout 0.0ms 959.9MB 4717ms 263ms pypy 3.10.16

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 1.ml 179ms 2.9ms 142.3MB 157ms 10ms ocaml 5.3.0
ocaml 2.ml 466ms 5.7ms 9.1MB 453ms 0ms ocaml 5.3.0
python 1.py 547ms 6.2ms 135.3MB 507ms 23ms pypy 3.10.16
python 2.py 723ms 2.9ms 164.2MB 683ms 27ms pyston 3.8.12
python 1.py 1065ms 10ms 86.0MB 1040ms 10ms pyston 3.8.12
python 2.py 1383ms 0.6ms 165.1MB 1343ms 27ms cpython 3.13.5
python 2.py 1508ms 4.4ms 290.3MB 1420ms 73ms pypy 3.10.16
python 1.py 2870ms 13ms 87.0MB 2847ms 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 2263ms 15ms 243.6MB 2203ms 47ms pypy 3.10.16
python 1.py 4758ms 1.8ms 252.5MB 4570ms 170ms pyston 3.8.12
ocaml 2.ml timeout 0.0ms 463.0MB 4823ms 163ms ocaml 5.3.0
python 1.py timeout 0.0ms 130.2MB 4930ms 60ms cpython 3.13.5

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
python 1.py 331ms 3.3ms 85.1MB 290ms 30ms pypy 3.10.16
python 1.py 510ms 17ms 30.3MB 477ms 20ms pyston 3.8.12
ocaml 2.ml 552ms 6.9ms 57.1MB 520ms 23ms ocaml 5.3.0
python 1.py 622ms 9.0ms 30.0MB 590ms 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 4567ms 4.6ms 6.4MB 4553ms 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 95.9MB 787ms 80ms pypy 3.10.16
python 8.py timeout 0.0ms 14.4MB 33ms 10ms pyston 3.8.12

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 1145ms 4.4ms 6.1MB 1137ms 0ms ocaml 5.3.0
python 8.py timeout 0.0ms 14.5MB 47ms 13ms cpython 3.13.5
python 8.py timeout 0.0ms 95.6MB 1280ms 180ms pypy 3.10.16
python 8.py timeout 0.0ms 13.6MB 60ms 13ms pyston 3.8.12

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
ocaml 2.ml 291ms 2.2ms 5.2MB 283ms 0ms ocaml 5.3.0
python 8-m.py 1948ms 18ms 92.9MB 6303ms 253ms pypy 3.10.16
python 8.py timeout 0.0ms 14.3MB 80ms 20ms cpython 3.13.5
python 8.py timeout 0.0ms 13.1MB 150ms 30ms pyston 3.8.12