diff --git a/internal/caches/storage_file.go b/internal/caches/storage_file.go
index 273a872..413ceb4 100644
--- a/internal/caches/storage_file.go
+++ b/internal/caches/storage_file.go
@@ -1156,11 +1156,16 @@ func (this *FileStorage) purgeLoop() {
 
 // 热点数据任务
 func (this *FileStorage) hotLoop() {
-	var memoryStorage = this.memoryStorage
+	var memoryStorage = this.memoryStorage // copy
 	if memoryStorage == nil {
 		return
 	}
 
+	// check memory space size
+	if !memoryStorage.HasFreeSpaceForHotItems() {
+		return
+	}
+
 	this.hotMapLocker.Lock()
 	if len(this.hotMap) == 0 {
 		this.hotMapLocker.Unlock()
diff --git a/internal/caches/storage_memory.go b/internal/caches/storage_memory.go
index ba4af46..65d9678 100644
--- a/internal/caches/storage_memory.go
+++ b/internal/caches/storage_memory.go
@@ -400,6 +400,11 @@ func (this *MemoryStorage) CanSendfile() bool {
 	return false
 }
 
+// HasFreeSpaceForHotItems 是否有足够的空间提供给热门内容
+func (this *MemoryStorage) HasFreeSpaceForHotItems() bool {
+	return atomic.LoadInt64(&this.usedSize) < this.memoryCapacityBytes()*3/4
+}
+
 // 计算Key Hash
 func (this *MemoryStorage) hash(key string) uint64 {
 	return xxhash.Sum64String(key)