Swift VS C 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
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
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
swift 1.swift 2463ms 7.5ms 5.5MB 2453ms 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 2.3ms 5.5MB 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 139ms 1.6ms 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
c 1.c 1.0ms 0.0ms 1.3MB 0ms 0ms zigcc 0.14.1
c 1.c 1.2ms 0.1ms 2.1MB 0ms 0ms clang 14.0.0-1ubuntu1.1
c 1.c 1.2ms 0.0ms 2.1MB 0ms 0ms gcc 15.1.0
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
c 1-m.c 172ms 4.3ms 23.6MB 400ms 10ms gcc 15.1.0
c 1-m.c 295ms 5.0ms 25.7MB 1007ms 33ms clang 14.0.0-1ubuntu1.1
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
c 1-m.c 28ms 0.6ms 12.6MB 57ms 0ms gcc 15.1.0
c 1-m.c 37ms 1.7ms 15.0MB 107ms 0ms clang 14.0.0-1ubuntu1.1
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
c 8-i.c 267ms 0.8ms 1.5MB 260ms 0ms zigcc 0.14.1
c 8-i.c 301ms 1.4ms 2.1MB 290ms 0ms clang 14.0.0-1ubuntu1.1
c 2.c 309ms 1.5ms 2.3MB 300ms 0ms gcc 15.1.0
c 5.c 313ms 1.4ms 2.3MB 303ms 0ms gcc 15.1.0
c 2.c 313ms 1.7ms 1.5MB 307ms 0ms zigcc 0.14.1
c 5.c 316ms 0.6ms 2.1MB 310ms 0ms clang 14.0.0-1ubuntu1.1
c 5.c 316ms 2.1ms 1.5MB 310ms 0ms zigcc 0.14.1
c 2.c 319ms 2.0ms 2.1MB 310ms 0ms clang 14.0.0-1ubuntu1.1
c 8-i.c 336ms 1.3ms 2.3MB 330ms 0ms gcc 15.1.0
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
c 8-i.c 29ms 0.3ms 1.5MB 20ms 0ms zigcc 0.14.1
c 8-i.c 32ms 0.5ms 2.1MB 20ms 0ms clang 14.0.0-1ubuntu1.1
c 2.c 33ms 0.4ms 1.5MB 30ms 0ms zigcc 0.14.1
c 5.c 33ms 0.6ms 2.3MB 30ms 0ms gcc 15.1.0
c 2.c 34ms 0.7ms 2.3MB 30ms 0ms gcc 15.1.0
c 5.c 34ms 0.4ms 2.1MB 30ms 0ms clang 14.0.0-1ubuntu1.1
c 5.c 35ms 0.6ms 1.5MB 30ms 0ms zigcc 0.14.1
c 8-i.c 36ms 0.5ms 2.3MB 30ms 0ms gcc 15.1.0
c 2.c 36ms 3.1ms 2.1MB 30ms 0ms clang 14.0.0-1ubuntu1.1
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
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
swift 1.swift 1865ms 11ms 7.0MB 1853ms 0ms swift 6.1.2