This is an automated cherry-pick of tikv#9048

close tikv#9047

Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>

pkg/cache/ttl.go

@@ -16,6 +16,7 @@ package cache
 
 import (
 	"context"
+	"sync/atomic"
 	"time"
 
 	"github.com/pingcap/log"
@@ -37,18 +38,26 @@ type ttlCache struct {
 	items      map[interface{}]ttlCacheItem
 	ttl        time.Duration
 	gcInterval time.Duration
+	// isGCRunning is used to avoid running GC multiple times.
+	isGCRunning atomic.Bool
 }
 
 // NewTTL returns a new TTL cache.
 func newTTL(ctx context.Context, gcInterval time.Duration, duration time.Duration) *ttlCache {
 	c := &ttlCache{
+<<<<<<< HEAD
 		ctx:        ctx,
 		items:      make(map[interface{}]ttlCacheItem),
 		ttl:        duration,
 		gcInterval: gcInterval,
+=======
+		ctx:         ctx,
+		items:       make(map[any]ttlCacheItem),
+		ttl:         duration,
+		gcInterval:  gcInterval,
+		isGCRunning: atomic.Bool{},
+>>>>>>> c92da8364 (cache: lazy gc in ttl (#9048))
 	}
-
-	go c.doGC()
 	return c
 }
 
@@ -61,7 +70,9 @@ func (c *ttlCache) put(key interface{}, value interface{}) {
 func (c *ttlCache) putWithTTL(key interface{}, value interface{}, ttl time.Duration) {
 	c.Lock()
 	defer c.Unlock()
-
+	if len(c.items) == 0 && c.isGCRunning.CompareAndSwap(false, true) {
+		go c.doGC()
+	}
 	c.items[key] = ttlCacheItem{
 		value:  value,
 		expire: time.Now().Add(ttl),
@@ -161,6 +172,11 @@ func (c *ttlCache) doGC() {
 					}
 				}
 			}
+			if len(c.items) == 0 && c.isGCRunning.CompareAndSwap(true, false) {
+				c.Unlock()
+				log.Debug("TTL GC items is empty exit")
+				return
+			}
 			c.Unlock()
 			log.Debug("TTL GC items", zap.Int("count", count))
 		case <-c.ctx.Done():