D VS Nim 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
nim 2.nim 786ms 11ms 34.9MB 770ms 3ms nim 2.2.4
nim 2.nim 947ms 6.3ms 35.2MB 923ms 10ms nim/clang 2.2.4
d 1.d 2199ms 4.7ms 312.4MB 2163ms 43ms ldc2 1.41.0
d 1.d 3022ms 5.5ms 314.5MB 3190ms 57ms dmd 2.111.0

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 73ms 0.2ms 5.5MB 60ms 0ms nim 2.2.4
nim 2.nim 93ms 1.5ms 5.8MB 80ms 0ms nim/clang 2.2.4
d 1.d 205ms 3.7ms 207.6MB 177ms 17ms ldc2 1.41.0
d 1.d 262ms 2.2ms 211.2MB 230ms 17ms dmd 2.111.0

coro-prime-sieve

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d timeout 0.0ms 16.5MB 4960ms 30ms dmd 2.111.0
d 1.d timeout 0.0ms 15.3MB 4970ms 20ms ldc2 1.41.0
nim 1.nim timeout 0.0ms 574.4MB 2647ms 1873ms nim 2.2.4
nim 3.nim timeout 0.0ms 6.6MB 4990ms 0ms nim 2.2.4
nim 1.nim timeout 0.0ms 574.8MB 2590ms 1930ms nim/clang 2.2.4
nim 3.nim timeout 0.0ms 6.9MB 4983ms 0ms nim/clang 2.2.4

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 3.nim 903ms 4.5ms 4.0MB 893ms 0ms nim/clang 2.2.4
nim 3.nim 905ms 4.9ms 3.6MB 893ms 0ms nim 2.2.4
d 1.d 1063ms 16ms 10.2MB 1037ms 13ms ldc2 1.41.0
d 1.d 1368ms 10ms 12.1MB 1350ms 10ms dmd 2.111.0
nim 1.nim 4097ms 6.6ms 518.7MB 2123ms 1547ms nim/clang 2.2.4
nim 1.nim 4111ms 9.9ms 518.2MB 2133ms 1553ms nim 2.2.4

edigits

Input: 250001

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 2551ms 4.2ms 8.1MB 2540ms 0ms ldc2 1.41.0
d 1.d 2867ms 4.2ms 10.3MB 2857ms 0ms dmd 2.111.0

Input: 100000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 441ms 0.9ms 8.1MB 430ms 0ms ldc2 1.41.0
d 1.d 521ms 1.5ms 10.4MB 510ms 0ms dmd 2.111.0

fannkuch-redux

Input: 11

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1-im.d 377ms 1.9ms 3.0MB 1423ms 0ms ldc2 1.41.0
d 2-im.d 1130ms 21ms 3.0MB 4303ms 3ms ldc2 1.41.0
d 1-i.d 1488ms 1.6ms 2.9MB 1480ms 0ms ldc2 1.41.0
d 1.d 3115ms 16ms 2.9MB 3107ms 0ms ldc2 1.41.0
d 2-i.d 3226ms 2.2ms 2.9MB 3217ms 0ms ldc2 1.41.0
d 1.d 3535ms 4.3ms 4.6MB 3527ms 0ms dmd 2.111.0
d 1-im.d 4491ms 66ms 4.8MB 17510ms 0ms dmd 2.111.0
d 1-i.d timeout 0.0ms 4.6MB 4990ms 0ms dmd 2.111.0
d 2-i.d timeout 0.0ms 4.5MB 4990ms 0ms dmd 2.111.0
d 2-im.d timeout 0.0ms 4.9MB 19723ms 0ms dmd 2.111.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1-im.d 37ms 1.0ms 3.0MB 110ms 0ms ldc2 1.41.0
d 2-im.d 96ms 1.9ms 3.0MB 350ms 0ms ldc2 1.41.0
d 1-i.d 123ms 0.1ms 2.9MB 120ms 0ms ldc2 1.41.0
d 1.d 264ms 3.2ms 2.9MB 253ms 0ms ldc2 1.41.0
d 2-i.d 266ms 0.6ms 2.8MB 260ms 0ms ldc2 1.41.0
d 1.d 297ms 3.2ms 4.6MB 290ms 0ms dmd 2.111.0
d 1-im.d 377ms 1.2ms 4.9MB 1430ms 0ms dmd 2.111.0
d 2-im.d 527ms 0.8ms 4.9MB 2003ms 0ms dmd 2.111.0
d 1-i.d 882ms 15ms 4.6MB 873ms 0ms dmd 2.111.0
d 2-i.d 1390ms 1.3ms 4.6MB 1380ms 0ms dmd 2.111.0

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 111ms 2.1ms 2.9MB 100ms 0ms ldc2 1.41.0
nim 2.nim 188ms 2.6ms 1.5MB 177ms 0ms nim 2.2.4
nim 2.nim 243ms 2.2ms 1.8MB 233ms 0ms nim/clang 2.2.4
nim 1.nim 537ms 2.6ms 1.8MB 447ms 73ms nim/clang 2.2.4
nim 1.nim 560ms 2.7ms 1.5MB 470ms 73ms nim 2.2.4
d 1.d 640ms 2.7ms 4.6MB 630ms 0ms dmd 2.111.0

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 14ms 0.5ms 2.9MB 10ms 0ms ldc2 1.41.0
nim 2.nim 21ms 0.8ms 1.5MB 10ms 0ms nim 2.2.4
nim 2.nim 27ms 1.0ms 1.8MB 20ms 0ms nim/clang 2.2.4
nim 1.nim 57ms 0.9ms 1.8MB 40ms 0ms nim/clang 2.2.4
nim 1.nim 59ms 0.7ms 1.5MB 47ms 0ms nim 2.2.4
d 1.d 68ms 0.4ms 4.8MB 60ms 0ms dmd 2.111.0

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 1.8MB 0ms 0ms nim/clang 2.2.4
d 1.d 1.6ms 0.1ms 3.0MB 0ms 0ms ldc2 1.41.0
d 1.d 2.1ms 0.2ms 5.1MB 0ms 0ms dmd 2.111.0

json-serde

Input: sample 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 2.d 59ms 0.6ms 15.7MB 63ms 7ms ldc2 1.41.0
d 2.d 239ms 2.1ms 22.7MB 237ms 7ms dmd 2.111.0

Input: canada 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 2.d 464ms 3.4ms 139.5MB 433ms 27ms ldc2 1.41.0
d 2.d 2474ms 8.3ms 158.3MB 2493ms 30ms dmd 2.111.0

knucleotide

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1-m.d 643ms 26ms 48.5MB 2040ms 13ms ldc2 1.41.0
d 1-m.d 1937ms 33ms 50.0MB 5567ms 10ms dmd 2.111.0

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1-m.d 95ms 8.6ms 39.5MB 253ms 23ms ldc2 1.41.0
d 1-m.d 211ms 7.1ms 39.9MB 597ms 10ms dmd 2.111.0

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 112ms 1.7ms 1.6MB 103ms 0ms nim/clang 2.2.4
nim 2.nim 114ms 2.9ms 1.4MB 110ms 0ms nim 2.2.4
d 1.d 130ms 0.9ms 6.2MB 120ms 0ms ldc2 1.41.0
d 1.d 175ms 1.9ms 7.9MB 163ms 3ms dmd 2.111.0
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 324ms 2.4ms 1.9MB 317ms 0ms nim/clang 2.2.4
nim 2.nim 338ms 4.4ms 1.4MB 330ms 0ms nim 2.2.4
d 1.d 377ms 2.3ms 5.9MB 367ms 10ms ldc2 1.41.0
d 1.d 510ms 2.0ms 7.9MB 497ms 10ms dmd 2.111.0
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 0.2ms 1.5MB 40ms 0ms nim/clang 2.2.4
nim 2.nim 51ms 1.6ms 1.3MB 40ms 0ms nim 2.2.4
d 1.d 58ms 0.4ms 5.9MB 50ms 0ms ldc2 1.41.0
d 1.d 80ms 0.5ms 8.1MB 70ms 0ms dmd 2.111.0
nim 1.nim 476ms 2.4ms 1.3MB 467ms 0ms nim 2.2.4
nim 1.nim 479ms 9.7ms 1.5MB 470ms 0ms nim/clang 2.2.4

mandelbrot

Input: 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 367ms 1.1ms 6.5MB 353ms 0ms ldc2 1.41.0
nim 1.nim 387ms 0.9ms 4.8MB 380ms 0ms nim/clang 2.2.4
nim 1.nim 576ms 1.6ms 4.5MB 567ms 0ms nim 2.2.4
d 1.d 2143ms 64ms 9.4MB 2130ms 0ms dmd 2.111.0

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 18ms 0.3ms 3.0MB 10ms 0ms ldc2 1.41.0
nim 1.nim 19ms 0.4ms 1.9MB 10ms 0ms nim/clang 2.2.4
nim 1.nim 27ms 0.2ms 1.6MB 20ms 0ms nim 2.2.4
d 1.d 92ms 2.4ms 4.6MB 87ms 0ms dmd 2.111.0

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 547ms 6.1ms 33.9MB 527ms 3ms nim 2.2.4
nim 1.nim 645ms 20ms 34.7MB 623ms 7ms nim/clang 2.2.4
d 1.d 1096ms 2.5ms 312.7MB 1057ms 40ms ldc2 1.41.0
d 1.d 1850ms 6.1ms 314.9MB 1977ms 50ms dmd 2.111.0

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 116ms 3.2ms 9.6MB 103ms 0ms nim 2.2.4
nim 1.nim 136ms 5.6ms 9.9MB 123ms 0ms nim/clang 2.2.4
d 1.d 230ms 1.2ms 312.7MB 190ms 27ms ldc2 1.41.0
d 1.d 359ms 1.7ms 315.0MB 327ms 27ms dmd 2.111.0

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 320ms 1.7ms 1.8MB 310ms 0ms nim 2.2.4
nim 2.nim 343ms 3.6ms 2.0MB 337ms 0ms nim/clang 2.2.4
d 1.d 360ms 0.2ms 2.9MB 350ms 0ms ldc2 1.41.0
d 2.d 361ms 1.9ms 2.9MB 350ms 0ms ldc2 1.41.0
d 1.d 678ms 2.2ms 4.6MB 670ms 0ms dmd 2.111.0
d 2.d 2033ms 7.7ms 4.8MB 2023ms 0ms dmd 2.111.0

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 2.nim 35ms 0.8ms 1.8MB 30ms 0ms nim 2.2.4
nim 2.nim 36ms 0.6ms 2.0MB 30ms 0ms nim/clang 2.2.4
d 2.d 38ms 0.3ms 2.9MB 30ms 0ms ldc2 1.41.0
d 1.d 39ms 0.4ms 2.9MB 30ms 0ms ldc2 1.41.0
d 1.d 72ms 0.1ms 4.8MB 60ms 0ms dmd 2.111.0
d 2.d 207ms 2.8ms 4.8MB 197ms 0ms dmd 2.111.0

nsieve

Input: 12

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 271ms 4.0ms 41.5MB 263ms 0ms nim 2.2.4
d 1.d 300ms 2.3ms 45.7MB 287ms 0ms ldc2 1.41.0
nim 1.nim 322ms 6.8ms 41.8MB 313ms 0ms nim/clang 2.2.4
d 1.d 347ms 3.8ms 79.3MB 333ms 3ms dmd 2.111.0
d 2.d 843ms 2.4ms 49.7MB 830ms 3ms ldc2 1.41.0
d 2.d 1172ms 3.3ms 49.3MB 1157ms 3ms dmd 2.111.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 52ms 2.4ms 11.5MB 43ms 0ms nim 2.2.4
d 1.d 64ms 3.3ms 15.7MB 53ms 0ms ldc2 1.41.0
nim 1.nim 66ms 4.2ms 11.8MB 57ms 0ms nim/clang 2.2.4
d 1.d 76ms 1.6ms 25.2MB 63ms 0ms dmd 2.111.0
d 2.d 213ms 1.6ms 17.7MB 200ms 0ms ldc2 1.41.0
d 2.d 291ms 1.5ms 19.6MB 280ms 0ms dmd 2.111.0

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 2431ms 4.5ms 8.1MB 2407ms 407ms ldc2 1.41.0
d 1.d 4429ms 9.8ms 10.5MB 4377ms 480ms dmd 2.111.0

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 584ms 4.3ms 8.1MB 563ms 103ms ldc2 1.41.0
d 1.d 1055ms 3.8ms 10.3MB 1050ms 97ms dmd 2.111.0

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 3.d 583ms 1.9ms 174.2MB 767ms 27ms ldc2 1.41.0
d 3.d 1212ms 9.4ms 177.2MB 1397ms 27ms dmd 2.111.0
nim 1.nim 1646ms 10ms 152.3MB 1613ms 20ms nim/clang 2.2.4
nim 1.nim 1673ms 4.5ms 151.5MB 1643ms 13ms nim 2.2.4

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 3.d 65ms 0.3ms 27.6MB 77ms 0ms ldc2 1.41.0
d 3.d 126ms 1.3ms 31.7MB 133ms 7ms dmd 2.111.0
nim 1.nim 173ms 2.5ms 17.5MB 160ms 0ms nim/clang 2.2.4
nim 1.nim 177ms 0.6ms 17.4MB 160ms 0ms nim 2.2.4

secp256k1

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 4782ms 7.8ms 4.0MB 4757ms 360ms ldc2 1.41.0
d 1.d timeout 0.0ms 6.5MB 4963ms 290ms dmd 2.111.0

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
d 1.d 1196ms 6.4ms 3.9MB 1190ms 77ms ldc2 1.41.0
d 1.d 2035ms 6.3ms 6.8MB 2023ms 110ms dmd 2.111.0

spectral-norm

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 3589ms 2.6ms 1.6MB 3580ms 0ms nim/clang 2.2.4
d 1.d 3594ms 2.3ms 4.0MB 3583ms 0ms ldc2 1.41.0
nim 1.nim 3610ms 3.4ms 1.4MB 3600ms 0ms nim 2.2.4
d 1.d 3630ms 25ms 5.9MB 3620ms 0ms dmd 2.111.0

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 899ms 0.6ms 1.5MB 890ms 0ms nim/clang 2.2.4
d 1.d 901ms 0.5ms 3.5MB 890ms 0ms ldc2 1.41.0
nim 1.nim 904ms 3.3ms 1.3MB 893ms 0ms nim 2.2.4
d 1.d 920ms 0.8ms 5.3MB 910ms 0ms dmd 2.111.0

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
nim 1.nim 226ms 0.2ms 1.5MB 220ms 0ms nim/clang 2.2.4
d 1.d 227ms 0.1ms 3.3MB 220ms 0ms ldc2 1.41.0
nim 1.nim 228ms 1.1ms 1.3MB 220ms 0ms nim 2.2.4
d 1.d 233ms 1.1ms 4.9MB 220ms 0ms dmd 2.111.0