enhance: cache store prefetch check exist

pkg/chunk/cached_store.go

@@ -819,6 +819,9 @@ func NewCachedStore(storage object.ObjectStorage, config Config, reg prometheus.
 		if size == 0 || size > store.conf.BlockSize {
 			return
 		}
+		if store.bcache.exist(key) {
+			return
+		}
 		p := NewOffPage(size)
 		defer p.Release()
 		_ = store.load(key, p, true, true)

pkg/chunk/disk_cache.go

@@ -631,6 +631,28 @@ func (cache *cacheStore) load(key string) (ReadCloser, error) {
 	return f, err
 }
 
+func (cache *cacheStore) exist(key string) bool {
+	cache.Lock()
+	if _, ok := cache.pages[key]; ok {
+		cache.Unlock()
+		return true
+	}
+	if cache.scanned {
+		k := cache.getCacheKey(key)
+		exist := cache.keys[k].atime > 0
+		cache.Unlock()
+		return exist
+	}
+	cache.Unlock()
+
+	var err error
+	err = cache.checkErr(func() error {
+		_, err = os.Stat(cache.cachePath(key))
+		return err
+	})
+	return err == nil
+}
+
 func (cache *cacheStore) cachePath(key string) string {
 	return filepath.Join(cache.dir, cacheDir, key)
 }
@@ -1013,6 +1035,7 @@ type CacheManager interface {
 	cache(key string, p *Page, force, dropCache bool)
 	remove(key string, staging bool)
 	load(key string) (ReadCloser, error)
+	exist(key string) bool
 	uploaded(key string, size int)
 	stage(key string, data []byte, keepCache bool) (string, error)
 	removeStage(key string) error
@@ -1192,6 +1215,14 @@ func (m *cacheManager) load(key string) (ReadCloser, error) {
 	return r, err
 }
 
+func (m *cacheManager) exist(key string) bool {
+	store := m.getStore(key)
+	if store == nil {
+		return false
+	}
+	return store.exist(key)
+}
+
 func (m *cacheManager) remove(key string, staging bool) {
 	store := m.getStore(key)
 	if store != nil {

pkg/chunk/disk_cache_test.go

@@ -332,6 +332,9 @@ func TestCacheManager(t *testing.T) {
 	defer p1.Release()
 	m.cache(k1, p1, true, false)
 
+	exist := m.exist(k1)
+	require.True(t, exist)
+
 	s1 := m.getStore(k1)
 	require.NotNil(t, s1)
 

pkg/chunk/mem_cache.go

@@ -103,6 +103,9 @@ func (c *memcache) delete(key string, p *Page) {
 }
 
 func (c *memcache) remove(key string, staging bool) {
+	if c.capacity == 0 {
+		return
+	}
 	c.Lock()
 	defer c.Unlock()
 	if item, ok := c.pages[key]; ok {
@@ -112,6 +115,9 @@ func (c *memcache) remove(key string, staging bool) {
 }
 
 func (c *memcache) load(key string) (ReadCloser, error) {
+	if c.capacity == 0 {
+		return nil, errors.New("not found")
+	}
 	c.Lock()
 	defer c.Unlock()
 	if item, ok := c.pages[key]; ok {
@@ -121,6 +127,16 @@ func (c *memcache) load(key string) (ReadCloser, error) {
 	return nil, errors.New("not found")
 }
 
+func (c *memcache) exist(key string) bool {
+	if c.capacity == 0 {
+		return false
+	}
+	c.Lock()
+	_, ok := c.pages[key]
+	c.Unlock()
+	return ok
+}
+
 // locked
 func (c *memcache) cleanup() {
 	var cnt int