add gc pause tests

.github/workflows/gcpause.yml

@@ -0,0 +1,38 @@
+name: gcpause
+
+on:
+  schedule:
+    - cron: '0 0 * * *'
+  push:
+    branches:
+      - master
+
+jobs:
+  gcpause:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        name: [nottl, phuslu, lxzan, ristretto, freelru, ecache, otter, theine, cloudflare, ccache, hashicorp]
+        cachesize: [100000, 200000, 400000, 1000000]
+    steps:
+      - name: Install packages
+        run: sudo apt update -y && sudo apt-get install -y csvkit datamash
+      - uses: actions/setup-go@v4
+        with:
+          go-version: '1.22'
+          check-latest: true
+      - uses: actions/checkout@v4
+      - name: go mod tidy
+        run: |
+          mkdir bench
+          cd bench
+          awk '{if($0 ~ "// gcpause.go"){a=1;b=1};if($0 ~ "```" && b=1){b=0};if (a&&b) {print}}' ../README.md > gcpause.go
+          go mod init bench
+          go mod tidy
+          go mod edit -replace github.com/phuslu/lru=../
+          cat go.mod
+      - name: GC Tests
+        working-directory: ./bench
+        run: |
+          echo -e 'GCStats\tCacheSize\tPause' > gcpause.txt
+          go run gcpause.go ${{ matrix.name }} ${{ matrix.cachesize }}

README.md

@@ -667,6 +667,168 @@ func SetupHashicorp(cachesize int) {
 - ristretto employs a questionable usage pattern due to its rejection of items via a bloom filter, resulting in a lower hit ratio.
 - freelru overcommits the cache size to the next power of 2, leading to higher memory usage particularly at larger cache sizes.
 
+### GC pause
+
+The GC pause result as below. Check github [gcpause][gcpause] action for more results and details.
+<details>
+  <summary>GC pause on keysize=16(string), valuesize=8(int), cachesize in (100000,200000,400000,1000000)</summary>
+
+```go
+// gcpause.go
+package main
+
+import (
+	"fmt"
+	"os"
+	"runtime"
+	"runtime/debug"
+	"strconv"
+	"time"
+
+	theine "github.com/Yiling-J/theine-go"
+	"github.com/cespare/xxhash/v2"
+	cloudflare "github.com/cloudflare/golibs/lrucache"
+	ristretto "github.com/dgraph-io/ristretto"
+	freelru "github.com/elastic/go-freelru"
+	hashicorp "github.com/hashicorp/golang-lru/v2/expirable"
+	ccache "github.com/karlseguin/ccache/v3"
+	lxzan "github.com/lxzan/memorycache"
+	otter "github.com/maypok86/otter"
+	ecache "github.com/orca-zhang/ecache"
+	phuslu "github.com/phuslu/lru"
+)
+
+const keysize = 16
+const repeat = 100
+
+var keys []string
+
+func main() {
+	name := os.Args[1]
+	cachesize, _ := strconv.Atoi(os.Args[2])
+
+	keys = make([]string, cachesize)
+	for i := 0; i < cachesize; i++ {
+		keys[i] = fmt.Sprintf(fmt.Sprintf("%%0%dd", keysize), i)
+	}
+
+	setup := map[string]func(int){
+		"nottl":      SetupNottl,
+		"phuslu":     SetupPhuslu,
+		"freelru":    SetupFreelru,
+		"ristretto":  SetupRistretto,
+		"otter":      SetupOtter,
+		"lxzan":      SetupLxzan,
+		"ecache":     SetupEcache,
+		"cloudflare": SetupCloudflare,
+		"ccache":     SetupCcache,
+		"hashicorp":  SetupHashicorp,
+		"theine":     SetupTheine,
+	}[name]
+
+	runtime.GC()
+
+	var o debug.GCStats
+	debug.ReadGCStats(&o)
+
+	for i := 0; i < repeat; i++ {
+		setup(cachesize)
+	}
+
+	var s debug.GCStats
+	debug.ReadGCStats(&s)
+
+	fmt.Printf("%s %d %s\n", name, cachesize, s.PauseTotal-o.PauseTotal)
+}
+
+func SetupNottl(cachesize int) {
+	cache := phuslu.NewLRUCache[string, int](cachesize)
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i)
+	}
+}
+
+func SetupPhuslu(cachesize int) {
+	cache := phuslu.NewTTLCache[string, int](cachesize)
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i, time.Hour)
+	}
+}
+
+func SetupFreelru(cachesize int) {
+	cache, _ := freelru.NewSharded[string, int](uint32(cachesize), func(s string) uint32 { return uint32(xxhash.Sum64String(s)) })
+	for i := 0; i < cachesize; i++ {
+		cache.AddWithLifetime(keys[i], i, time.Hour)
+	}
+}
+
+func SetupOtter(cachesize int) {
+	cache, _ := otter.MustBuilder[string, int](cachesize).WithVariableTTL().Build()
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i, time.Hour)
+	}
+}
+
+func SetupEcache(cachesize int) {
+	cache := ecache.NewLRUCache(1024, uint16(cachesize/1024), time.Hour)
+	for i := 0; i < cachesize; i++ {
+		cache.Put(keys[i], i)
+	}
+}
+
+func SetupRistretto(cachesize int) {
+	cache, _ := ristretto.NewCache(&ristretto.Config{
+		NumCounters: int64(10 * cachesize), // number of keys to track frequency of (10M).
+		MaxCost:     int64(cachesize),      // maximum cost of cache (1M).
+		BufferItems: 64,                    // number of keys per Get buffer.
+	})
+	for i := 0; i < cachesize; i++ {
+		cache.SetWithTTL(keys[i], i, 1, time.Hour)
+	}
+}
+
+func SetupLxzan(cachesize int) {
+	cache := lxzan.New[string, int](
+		lxzan.WithBucketNum(128),
+		lxzan.WithBucketSize(cachesize/128, cachesize/128),
+		lxzan.WithInterval(time.Hour, time.Hour),
+	)
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i, time.Hour)
+	}
+}
+
+func SetupTheine(cachesize int) {
+	cache, _ := theine.NewBuilder[string, int](int64(cachesize)).Build()
+	for i := 0; i < cachesize; i++ {
+		cache.SetWithTTL(keys[i], i, 1, time.Hour)
+	}
+}
+
+func SetupCloudflare(cachesize int) {
+	cache := cloudflare.NewMultiLRUCache(1024, uint(cachesize/1024))
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i, time.Now().Add(time.Hour))
+	}
+}
+
+func SetupCcache(cachesize int) {
+	cache := ccache.New(ccache.Configure[int]().MaxSize(int64(cachesize)).ItemsToPrune(100))
+	for i := 0; i < cachesize; i++ {
+		cache.Set(keys[i], i, time.Hour)
+	}
+}
+
+func SetupHashicorp(cachesize int) {
+	cache := hashicorp.NewLRU[string, int](cachesize, nil, time.Hour)
+	for i := 0; i < cachesize; i++ {
+		cache.Add(keys[i], i)
+	}
+}
+```
+</details>
+
+
 ### Hit ratio
 It is a classic sharded LRU implementation, so the hit ratio is comparable to or slightly lower than a regular LRU.
 
@@ -684,5 +846,6 @@ For inquiries or support, contact [email protected] or raise github issues.
 [goreport]: https://goreportcard.com/report/github.com/phuslu/lru
 [benchmark]: https://github.com/phuslu/lru/actions/workflows/benchmark.yml
 [memory]: https://github.com/phuslu/lru/actions/workflows/memory.yml
+[gcpause]: https://github.com/phuslu/lru/actions/workflows/gcpause.yml
 [codecov-img]: https://codecov.io/gh/phuslu/lru/graph/badge.svg?token=Q21AMQNM1K
 [codecov]: https://codecov.io/gh/phuslu/lru