Swift VS Kotlin benchmarks

Current benchmark data was generated on Fri Aug 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
kotlin 1.kt 500ms 16ms 578.4MB 597ms 97ms kotlin/jvm 21
swift 1.swift 2661ms 31ms 53.6MB 2630ms 17ms swift 6.1.2
kotlin 1.kt 3911ms 6.4ms 143.8MB 4087ms 70ms kotlin/native 2.1.20

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 122ms 1.1ms 159.5MB 143ms 37ms kotlin/jvm 21
kotlin 1.kt 203ms 6.2ms 17.3MB 210ms 3ms kotlin/native 2.1.20
swift 1.swift 242ms 3.3ms 11.9MB 230ms 0ms swift 6.1.2

fannkuch-redux

Input: 11

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 1.swift 2469ms 4.7ms 5.4MB 2460ms 0ms swift 6.1.2

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 1.swift 213ms 0.4ms 6.1MB 200ms 0ms swift 6.1.2

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 3-m.swift 138ms 0.6ms 20.7MB 400ms 3ms swift 6.1.2

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 3.swift 37ms 0.3ms 14.2MB 30ms 0ms swift 6.1.2

helloworld

Input: QwQ

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 2.2ms 0.2ms 3.0MB 0ms 0ms kotlin/native 2.1.20
swift 1.swift 2.2ms 0.2ms 5.6MB 0ms 0ms swift 6.1.2
kotlin 1.kt 61ms 0.9ms 47.6MB 74ms 18ms kotlin/jvm 21

knucleotide

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 2-m.swift 1313ms 5.4ms 70.6MB 4803ms 27ms swift 6.1.2

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 2-m.swift 250ms 2.2ms 60.0MB 663ms 30ms swift 6.1.2

nbody

Input: 5000000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
swift 7.swift 343ms 0.8ms 9.9MB 330ms 0ms swift 6.1.2
kotlin 1n.kt 352ms 2.5ms 3.5MB 340ms 0ms kotlin/native 2.1.20
kotlin 1.kt 442ms 1.2ms 49.6MB 483ms 20ms kotlin/jvm 21

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1n.kt 39ms 0.6ms 3.5MB 30ms 0ms kotlin/native 2.1.20
swift 7.swift 39ms 0.1ms 9.8MB 30ms 0ms swift 6.1.2
kotlin 1-m.kt 118ms 1.3ms 49.6MB 160ms 20ms kotlin/jvm 21

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1.kt 3669ms 28ms 353.1MB 4487ms 113ms kotlin/jvm 21
kotlin 1n.kt timeout 0.0ms 26.6MB 3973ms 1500ms kotlin/native 2.1.20
kotlin 2n.kt timeout 0.0ms 30.9MB 5110ms 130ms kotlin/native 2.1.20
swift 1.swift timeout 0.0ms 7.3MB 4930ms 57ms swift 6.1.2

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
kotlin 1-m.kt 957ms 5.5ms 357.3MB 1767ms 90ms kotlin/jvm 21
swift 1.swift 1856ms 13ms 7.0MB 1847ms 0ms swift 6.1.2
kotlin 1n.kt timeout 0.0ms 26.8MB 3970ms 1513ms kotlin/native 2.1.20
kotlin 2n.kt timeout 0.0ms 30.6MB 5120ms 117ms kotlin/native 2.1.20