upgrade to xxh3 hashing pkg

_example/go.mod

@@ -1,6 +1,8 @@
 module github.com/go-chi/httprate/_example
 
-go 1.22.5
+go 1.23.0
+
+toolchain go1.24.1
 
 replace github.com/go-chi/httprate => ../
 
@@ -9,4 +11,8 @@ require (
 	github.com/go-chi/httprate v0.0.0-00010101000000-000000000000
 )
 
-require github.com/cespare/xxhash/v2 v2.3.0 // indirect
+require (
+	github.com/klauspost/cpuid/v2 v2.2.10 // indirect
+	github.com/zeebo/xxh3 v1.0.2 // indirect
+	golang.org/x/sys v0.30.0 // indirect
+)

_example/go.sum

@@ -1,6 +1,12 @@
-github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
-github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/go-chi/chi/v5 v5.1.0 h1:acVI1TYaD+hhedDJ3r54HyA6sExp3HfXq7QWEEY/xMw=
 github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
-golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
-golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+github.com/klauspost/cpuid/v2 v2.2.10 h1:tBs3QSyvjDyFTq3uoc/9xFpCuOsJQFNPiAhYdw2skhE=
+github.com/klauspost/cpuid/v2 v2.2.10/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=
+github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
+github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
+github.com/zeebo/xxh3 v1.0.2 h1:xZmwmqxHZA8AI603jOQ0tMqmBr9lPeFwGg6d+xy9DC0=
+github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
+golang.org/x/sync v0.12.0 h1:MHc5BpPuC30uJk597Ri8TV3CNZcTLu6B6z4lJy+g6Jw=
+golang.org/x/sync v0.12.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
+golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
+golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=

go.mod

@@ -1,7 +1,14 @@
 module github.com/go-chi/httprate
 
-go 1.17
+go 1.23.0
 
-require github.com/cespare/xxhash/v2 v2.3.0
+toolchain go1.24.1
 
-require golang.org/x/sync v0.7.0 // indirect
+require github.com/zeebo/xxh3 v1.0.2
+
+require golang.org/x/sys v0.30.0 // indirect
+
+require (
+	github.com/klauspost/cpuid/v2 v2.2.10 // indirect
+	golang.org/x/sync v0.12.0
+)

go.sum

@@ -1,6 +1,10 @@
-github.com/cespare/xxhash/v2 v2.1.2 h1:YRXhKfTDauu4ajMg1TPgFO5jnlC2HCbmLXMcTG5cbYE=
-github.com/cespare/xxhash/v2 v2.1.2/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
-github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
-github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
-golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
-golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+github.com/klauspost/cpuid/v2 v2.2.10 h1:tBs3QSyvjDyFTq3uoc/9xFpCuOsJQFNPiAhYdw2skhE=
+github.com/klauspost/cpuid/v2 v2.2.10/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=
+github.com/zeebo/assert v1.3.0 h1:g7C04CbJuIDKNPFHmsk4hwZDO5O+kntRxzaUoNXj+IQ=
+github.com/zeebo/assert v1.3.0/go.mod h1:Pq9JiuJQpG8JLJdtkwrJESF0Foym2/D9XMU5ciN/wJ0=
+github.com/zeebo/xxh3 v1.0.2 h1:xZmwmqxHZA8AI603jOQ0tMqmBr9lPeFwGg6d+xy9DC0=
+github.com/zeebo/xxh3 v1.0.2/go.mod h1:5NWz9Sef7zIDm2JHfFlcQvNekmcEl9ekUZQQKCYaDcA=
+golang.org/x/sync v0.12.0 h1:MHc5BpPuC30uJk597Ri8TV3CNZcTLu6B6z4lJy+g6Jw=
+golang.org/x/sync v0.12.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
+golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
+golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=

limit_key.go

@@ -4,11 +4,11 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/cespare/xxhash/v2"
+	"github.com/zeebo/xxh3"
 )
 
 func LimitCounterKey(key string, window time.Time) uint64 {
-	h := xxhash.New()
+	h := xxh3.New()
 	h.WriteString(key)
 	h.WriteString(fmt.Sprintf("%d", window.Unix()))
 	return h.Sum64()

local_counter.go

@@ -4,7 +4,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/cespare/xxhash/v2"
+	"github.com/zeebo/xxh3"
 )
 
 // NewLocalLimitCounter creates an instance of localCounter,
@@ -71,8 +71,28 @@ func (c *localCounter) Increment(key string, currentWindow time.Time) error {
 	return c.IncrementBy(key, currentWindow, 1)
 }
 
+func (c *localCounter) evict(currentWindow time.Time) {
+	if c.latestWindow == currentWindow {
+		return
+	}
+
+	previousWindow := currentWindow.Add(-c.windowLength)
+	if c.latestWindow == previousWindow {
+		c.latestWindow = currentWindow
+		// Shift the windows without map re-allocation.
+		clear(c.previousCounters)
+		c.latestCounters, c.previousCounters = c.previousCounters, c.latestCounters
+		return
+	}
+
+	c.latestWindow = currentWindow
+
+	clear(c.previousCounters)
+	clear(c.latestCounters)
+}
+
 func limitCounterKey(key string) uint64 {
-	h := xxhash.New()
+	h := xxh3.New()
 	h.WriteString(key)
 	return h.Sum64()
 }