Swift VS Rust 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
rust 4.rs 1277ms 6.1ms 33.6MB 1253ms 10ms rustc 1.88.0
rust 5.rs 1404ms 46ms 33.8MB 1380ms 7ms rustc 1.88.0
rust 3.rs 1431ms 12ms 49.8MB 1400ms 13ms rustc 1.88.0
swift 1.swift 2692ms 22ms 53.8MB 2657ms 20ms swift 6.1.2

Input: 15

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 4.rs 122ms 2.6ms 5.6MB 110ms 0ms rustc 1.88.0
rust 5.rs 128ms 3.1ms 5.8MB 120ms 0ms rustc 1.88.0
rust 3.rs 137ms 3.2ms 7.8MB 127ms 0ms rustc 1.88.0
swift 1.swift 240ms 0.7ms 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
rust 3-im.rs 408ms 2.7ms 2.1MB 1570ms 0ms rustc 1.88.0
rust 5-m.rs 555ms 5.1ms 2.0MB 2160ms 0ms rustc 1.88.0
rust 2-im.rs 672ms 12ms 2.0MB 2567ms 0ms rustc 1.88.0
rust 1-m.rs 941ms 5.9ms 2.1MB 3617ms 0ms rustc 1.88.0
rust 3-i.rs 1506ms 1.0ms 1.9MB 1500ms 0ms rustc 1.88.0
rust 2-i.rs 2400ms 1.3ms 1.8MB 2390ms 0ms rustc 1.88.0
swift 1.swift 2463ms 7.5ms 5.5MB 2453ms 0ms swift 6.1.2
rust 1.rs 2723ms 24ms 1.8MB 2713ms 0ms rustc 1.88.0

Input: 10

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 3-im.rs 37ms 0.3ms 2.0MB 120ms 0ms rustc 1.88.0
rust 5-m.rs 52ms 0.9ms 2.1MB 170ms 0ms rustc 1.88.0
rust 2-im.rs 60ms 1.0ms 2.1MB 203ms 0ms rustc 1.88.0
rust 1-m.rs 81ms 1.2ms 2.1MB 290ms 0ms rustc 1.88.0
rust 3-i.rs 126ms 0.1ms 1.9MB 120ms 0ms rustc 1.88.0
rust 2-i.rs 198ms 0.3ms 1.8MB 190ms 0ms rustc 1.88.0
swift 1.swift 213ms 2.3ms 5.5MB 200ms 0ms swift 6.1.2
rust 1.rs 229ms 1.4ms 1.8MB 220ms 0ms rustc 1.88.0

fasta

Input: 2500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 6.rs 90ms 1.0ms 1.9MB 80ms 0ms rustc 1.88.0
rust 5c-m.rs 90ms 0.3ms 3.4MB 260ms 0ms rustc 1.88.0
rust 5-m.rs 91ms 0.4ms 3.2MB 273ms 0ms rustc 1.88.0
swift 3-m.swift 139ms 1.6ms 20.7MB 400ms 3ms swift 6.1.2
rust 1c.rs 161ms 0.2ms 1.9MB 150ms 0ms rustc 1.88.0
rust 1.rs 195ms 1.3ms 1.9MB 183ms 0ms rustc 1.88.0

Input: 250000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 6.rs 11ms 0.4ms 1.9MB 0ms 0ms rustc 1.88.0
rust 5c-m.rs 15ms 0.6ms 3.4MB 23ms 0ms rustc 1.88.0
rust 5-m.rs 16ms 0.4ms 3.2MB 27ms 0ms rustc 1.88.0
rust 1c.rs 19ms 0.4ms 1.9MB 10ms 0ms rustc 1.88.0
rust 1.rs 22ms 0.5ms 1.9MB 10ms 0ms rustc 1.88.0
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
rust 1.rs 1.2ms 0.0ms 1.8MB 0ms 0ms rustc 1.88.0
rust 1.rs 1.2ms 0.1ms 1.9MB 0ms 0ms rustc 1.90.0-nightly
swift 1.swift 2.4ms 0.1ms 5.6MB 0ms 0ms swift 6.1.2

knucleotide

Input: 2500000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 8-m.rs 227ms 16ms 27.6MB 660ms 13ms rustc 1.88.0
rust 8.rs 411ms 5.1ms 24.2MB 390ms 7ms rustc 1.88.0
swift 2-m.swift 1361ms 16ms 74.3MB 4960ms 37ms swift 6.1.2

Input: 250000_in

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 8-m.rs 33ms 3.8ms 15.8MB 60ms 7ms rustc 1.88.0
rust 8.rs 57ms 3.0ms 11.6MB 40ms 3ms rustc 1.88.0
swift 2-m.swift 251ms 2.0ms 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
rust 4-i.rs 164ms 0.5ms 1.8MB 160ms 0ms rustc 1.88.0
rust 7-i.rs 219ms 0.6ms 1.8MB 210ms 0ms rustc 1.88.0
rust 1.rs 229ms 0.2ms 1.8MB 220ms 0ms rustc 1.88.0
rust 3.rs 279ms 0.6ms 1.9MB 270ms 0ms rustc 1.90.0-nightly
rust 2.rs 279ms 0.4ms 1.8MB 270ms 0ms rustc 1.88.0
swift 7.swift 346ms 2.1ms 9.9MB 337ms 0ms swift 6.1.2

Input: 500000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 4-i.rs 19ms 0.1ms 1.8MB 10ms 0ms rustc 1.88.0
rust 7-i.rs 24ms 0.3ms 1.8MB 20ms 0ms rustc 1.88.0
rust 1.rs 25ms 0.4ms 1.8MB 20ms 0ms rustc 1.88.0
rust 3.rs 30ms 0.2ms 1.8MB 20ms 0ms rustc 1.90.0-nightly
rust 2.rs 30ms 0.3ms 1.6MB 20ms 0ms rustc 1.88.0
swift 7.swift 39ms 0.9ms 9.9MB 30ms 0ms swift 6.1.2

pidigits

Input: 8000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 1.rs 1530ms 10ms 2.7MB 1310ms 200ms rustc 1.88.0
rust 2.rs 1715ms 8.1ms 2.7MB 1627ms 77ms rustc 1.88.0
swift 1.swift timeout 0.0ms 7.3MB 4927ms 60ms swift 6.1.2

Input: 4000

lang code time stddev peak-mem mem time(user) time(sys) compiler compiler/runtime
rust 1.rs 321ms 0.5ms 2.4MB 297ms 10ms rustc 1.88.0
rust 2.rs 380ms 0.8ms 2.4MB 370ms 0ms rustc 1.88.0
swift 1.swift 1865ms 11ms 7.0MB 1853ms 0ms swift 6.1.2