GitHub - kelindar/intmap: Fast integer map for uint32-to-uint32

kelindar/intmap
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This repository contains an implementation of uint32-to-uint32 map which is ~20-50% faster than Go standard map for the same types (see benchmarks below). The code was based of Brent Pedersen's intintmap and the main logic remains intact, with some bug fixes and improvements of the API itself. The map is backed by a single array which interleaves keys and values to improve data locality.

Usage

// Create a new map with capacity of 1024 (resizeable) and 90% desired fill rate
m := intmap.NewWithFill(1024, 0.90)

// Store a few key/value pairs
m.Store(1, 100)
m.Store(2, 200)

// Load them
v, ok := m.Load(1)
v, ok := m.Load(2)

// Delete keys
m.Delete(1)
m.Delete(2)

Benchmarks

Looking at the benchmarks agains the standard Go map, this map should perform roughly 20-50% better depending on the conditions.

cpu: 13th Gen Intel(R) Core(TM) i7-13700K
BenchmarkStore/intmap-24         	144682518	        8.203 ns/op	       0 B/op	       0 allocs/op
BenchmarkStore/sync-24           	47746893	        24.78 ns/op	       0 B/op	       0 allocs/op
BenchmarkStore/stdmap-24         	65009140	        17.73 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/intmap-0%-24         	40558078	        28.98 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/sync-0%-24           	36516896	        31.53 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/stdmap-0%-24         	76847426	        15.57 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/intmap-10%-24        	40846196	        28.31 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/sync-10%-24          	37622625	        31.21 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/stdmap-10%-24        	69917145	        16.90 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/intmap-50%-24        	52405636	        21.62 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/sync-50%-24          	44567251	        25.75 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/stdmap-50%-24        	50478930	        23.68 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/intmap-90%-24        	140594277	        8.486 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/sync-90%-24          	83630574	        14.40 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/stdmap-90%-24        	69522844	        17.17 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/intmap-100%-24       	189147504	        6.271 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/sync-100%-24         	88044195	        13.58 ns/op	       0 B/op	       0 allocs/op
BenchmarkLoad/stdmap-100%-24       	78736231	        15.12 ns/op	       0 B/op	       0 allocs/op