Results for 38 of 40 languages from this run on actest1.

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C# VS Kotlin benchmarks

Current benchmark data was generated on Sun Sep 27 2026, full log can be found HERE

CONTRIBUTIONS are WELCOME!

[x86_64][4 cores] Intel(R) Core(TM) i7-3687U CPU @ 2.10GHz (Model 58)

* -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 794ms 80ms 581.9MB 1017ms 130ms kotlin/jvm 21.0.12
csharp 1.cs 1295ms 11ms 187.1MB 1320ms 160ms dotnet 9.0.318

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 188ms 30ms 159.7MB 233ms 30ms kotlin/jvm 21.0.12
csharp 1.cs 287ms 27ms 55.0MB 213ms 33ms dotnet 9.0.318

coro-prime-sieve

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 2-m.kt 3342ms 283ms 229.6MB 12590ms 123ms kotlin/jvm 21.0.12
csharp 1-m.cs 3524ms 240ms 77.2MB 12327ms 143ms dotnet 9.0.318
kotlin 1.kt 3615ms 290ms 219.6MB 4723ms 107ms kotlin/jvm 21.0.12

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1-m.cs 433ms 30ms 41.3MB 1257ms 27ms dotnet 9.0.318
kotlin 1-m.kt 738ms 7.2ms 77.4MB 1727ms 47ms kotlin/jvm 21.0.12
kotlin 2-m.kt 1625ms 206ms 97.5MB 5807ms 100ms kotlin/jvm 21.0.12

edigits

Input: 250001

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 8169ms 4.7ms 39.1MB 8167ms 20ms dotnet 9.0.318

Input: 100000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 1436ms 18ms 36.0MB 1407ms 10ms dotnet 9.0.318

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 5-m.cs 228ms 1.4ms 45.9MB 590ms 100ms dotnet 9.0.318

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 5-m.cs 89ms 8.4ms 41.0MB 130ms 10ms dotnet 9.0.318

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 46ms 3.5ms 24.6MB 30ms 2ms dotnet 9.0.318
kotlin 1-m.kt 87ms 4.3ms 46.2MB 136ms 12ms kotlin/jvm 21.0.12

http-server

Input: 3000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2-http2.cs 821ms 13ms 108.9MB 1357ms 167ms dotnet 9.0.318
csharp 2-m.cs 1078ms 79ms 166.0MB 1467ms 757ms dotnet 9.0.318
csharp 1-m.cs 1153ms 50ms 167.4MB 1897ms 800ms dotnet 9.0.318
csharp 2-http3.cs 1186ms 29ms 170.6MB 2087ms 340ms dotnet 9.0.318
kotlin 2-m.kt 9841ms 283ms 341.7MB 32387ms 3343ms kotlin/jvm 21.0.12
kotlin 1-m.kt 11376ms 242ms 433.1MB 37790ms 4520ms kotlin/jvm 21.0.12

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 608ms 17ms 87.8MB 637ms 177ms dotnet 9.0.318
csharp 1-m.cs 656ms 17ms 100.2MB 873ms 230ms dotnet 9.0.318
csharp 2-http2.cs 679ms 17ms 90.2MB 780ms 113ms dotnet 9.0.318
csharp 2-http3.cs 868ms 13ms 100.2MB 1010ms 147ms dotnet 9.0.318
kotlin 2-m.kt 3791ms 276ms 249.0MB 11797ms 810ms kotlin/jvm 21.0.12
kotlin 1-m.kt 3917ms 180ms 275.4MB 12153ms 857ms kotlin/jvm 21.0.12

json-serde

Input: sample 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 503ms 28ms 73.7MB 480ms 30ms dotnet 9.0.318
csharp 1.cs 1142ms 104ms 145.0MB 1297ms 93ms dotnet 9.0.318
kotlin 1-m.kt 1371ms 105ms 176.1MB 3830ms 140ms kotlin/jvm 21.0.12

Input: canada 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 2313ms 114ms 247.2MB 2667ms 93ms dotnet 9.0.318
kotlin 1-m.kt 3079ms 117ms 749.4MB 7240ms 250ms kotlin/jvm 21.0.12
csharp 1-m.cs 3652ms 36ms 762.3MB 5157ms 397ms dotnet 9.0.318

knucleotide

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 6-m.cs 1157ms 42ms 72.1MB 2957ms 37ms dotnet 9.0.318

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 6-m.cs 289ms 10ms 58.9MB 450ms 33ms dotnet 9.0.318

lru

Input: 1000 1000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 284ms 4.7ms 95.4MB 503ms 33ms kotlin/jvm 21.0.12
csharp 2.cs 293ms 15ms 32.0MB 273ms 13ms dotnet 9.0.318
kotlin 2-m.kt 389ms 13ms 99.5MB 863ms 27ms kotlin/jvm 21.0.12
csharp 1.cs 2152ms 98ms 36.0MB 2140ms 20ms dotnet 9.0.318

Input: 1000 3000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 482ms 4.8ms 201.4MB 717ms 47ms kotlin/jvm 21.0.12
csharp 2.cs 484ms 2.4ms 29.8MB 463ms 13ms dotnet 9.0.318
kotlin 2-m.kt 543ms 5.7ms 209.8MB 993ms 67ms kotlin/jvm 21.0.12
csharp 1.cs 6072ms 312ms 36.0MB 6053ms 30ms dotnet 9.0.318

Input: 100 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 203ms 0.2ms 31.9MB 180ms 10ms dotnet 9.0.318
kotlin 1-m.kt 255ms 1.9ms 91.1MB 500ms 37ms kotlin/jvm 21.0.12
kotlin 2-m.kt 302ms 15ms 95.4MB 693ms 23ms kotlin/jvm 21.0.12
csharp 1.cs 4300ms 12ms 33.1MB 4280ms 20ms dotnet 9.0.318

mandelbrot

Input: 5000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 4.cs 1297ms 11ms 38.9MB 1273ms 10ms dotnet 9.0.318
csharp 2.cs 1353ms 3.1ms 40.1MB 1333ms 13ms dotnet 9.0.318
csharp 3.cs 3774ms 86ms 39.8MB 3747ms 10ms dotnet 9.0.318
csharp 1.cs 3878ms 86ms 39.6MB 3857ms 7ms dotnet 9.0.318

Input: 1000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 4.cs 177ms 2.6ms 35.9MB 153ms 17ms dotnet 9.0.318
csharp 1.cs 231ms 2.8ms 34.9MB 207ms 10ms dotnet 9.0.318
csharp 3.cs 268ms 2.2ms 34.6MB 237ms 20ms dotnet 9.0.318
csharp 2.cs 295ms 8.0ms 37.0MB 277ms 7ms dotnet 9.0.318

merkletrees

Input: 17

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 641ms 8.2ms 676.7MB 820ms 93ms kotlin/jvm 21.0.12
csharp 2.cs 904ms 34ms 135.4MB 880ms 93ms dotnet 9.0.318
csharp 1.cs 1035ms 40ms 163.4MB 1010ms 123ms dotnet 9.0.318

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 250ms 11ms 205.0MB 363ms 67ms kotlin/jvm 21.0.12
csharp 2.cs 304ms 5.8ms 74.7MB 257ms 57ms dotnet 9.0.318
csharp 1.cs 337ms 4.6ms 93.7MB 303ms 57ms dotnet 9.0.318

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 8.cs 783ms 1.5ms 29.6MB 760ms 10ms dotnet 9.0.318
kotlin 1.kt 884ms 6.3ms 49.9MB 980ms 17ms kotlin/jvm 21.0.12
csharp 9.cs 997ms 4.7ms 29.6MB 967ms 17ms dotnet 9.0.318

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 8.cs 159ms 7.2ms 30.1MB 140ms 3ms dotnet 9.0.318
kotlin 1-m.kt 208ms 14ms 49.7MB 297ms 17ms kotlin/jvm 21.0.12
csharp 9.cs 228ms 3.1ms 29.9MB 203ms 10ms dotnet 9.0.318

nsieve

Input: 12

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 819ms 3.8ms 33.5MB 797ms 13ms dotnet 9.0.318
csharp 1.cs 1042ms 3.6ms 96.6MB 1020ms 13ms dotnet 9.0.318

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 2.cs 205ms 0.9ms 32.5MB 183ms 7ms dotnet 9.0.318
csharp 1.cs 235ms 2.8ms 37.6MB 213ms 10ms dotnet 9.0.318

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 4990ms 415ms 40.2MB 4877ms 317ms dotnet 9.0.318
kotlin 1.kt 5427ms 177ms 419.0MB 6873ms 170ms kotlin/jvm 21.0.12

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 1338ms 83ms 39.5MB 1447ms 73ms dotnet 9.0.318
kotlin 1-m.kt 1629ms 66ms 362.2MB 3007ms 117ms kotlin/jvm 21.0.12

regex-redux

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 5.cs 2515ms 24ms 440.0MB 2690ms 250ms dotnet 9.0.318
csharp 6.cs 3319ms 218ms 437.6MB 3393ms 273ms dotnet 9.0.318
kotlin 1.kt 8673ms 241ms 178.9MB 9617ms 70ms kotlin/jvm 21.0.12

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 5.cs 394ms 5.1ms 73.8MB 370ms 33ms dotnet 9.0.318
csharp 6.cs 560ms 7.0ms 75.4MB 530ms 33ms dotnet 9.0.318
kotlin 1-m.kt 1293ms 57ms 133.7MB 2110ms 47ms kotlin/jvm 21.0.12

secp256k1

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 4071ms 82ms 37.6MB 4150ms 47ms dotnet 9.0.318
kotlin 1.kt 5266ms 83ms 228.7MB 6800ms 87ms kotlin/jvm 21.0.12

Input: 500

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 1.cs 1287ms 120ms 37.8MB 1393ms 27ms dotnet 9.0.318
kotlin 1-m.kt 1750ms 44ms 260.1MB 2960ms 50ms kotlin/jvm 21.0.12

spectral-norm

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 3-m.cs 5928ms 20ms 33.5MB 23127ms 17ms dotnet 9.0.318

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 3-m.cs 1536ms 1.6ms 34.0MB 5793ms 13ms dotnet 9.0.318

Input: 2000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
csharp 3-m.cs 449ms 3.7ms 33.3MB 1487ms 17ms dotnet 9.0.318