#bench-simple-regexp A benchmark to compare using Regular Expressions with a strings.Index to find a single substring in a string.

For the Regular Expressions benchmarks, there are two implementations: one does a regexp.Compile() and uses the resulting object, the other uses a pre-compiled RegExp.

The findWIndexBuf() func fills a pre-allocated slice.

The string to be searched is the output of running VBoxManage showvminfo <machinename> --machinereadable

Results

This is on a single-core VM running Jessie w LXDE desktop and 8GB of RAM. The CPU is an Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz.

Name                            Iterations 
--------------------------------------------------------------------------------------------------------------
BenchmarkFindWRegExp              100000             17057 ns/op           44480 B/op         42 allocs/op
BenchmarkFindWRegExpPrecompiled   500000              2243 ns/op              64 B/op          2 allocs/op
BenchmarkFindWIndex              2000000               824 ns/op              32 B/op          1 allocs/op
BenchmarkFindWIndexBuf           2000000               731 ns/op               0 B/op          0 allocs/op