@@ -0,0 +13,4 @@
+		case <-c.closeCh:
+			return
+		case <-t.C:
+			for {

@@ -0,0 +39,4 @@
+func (c *cache) runFlushLoop() {
+	ch := c.closeCh
+	c.wg.Add(1)
+	go func() {

@@ -126,6 +128,7 @@ type shardCfg struct {
 
 	writecacheCfg struct {
 		enabled          bool
+		typ              writecacheconfig.Type

@@ -0,0 +118,4 @@
+	var err error
+	if c.db != nil {
+		err = c.db.Close()
+		if err != nil {

@@ -719,2 +714,2 @@
-			writecache.WithLogger(c.log),
-		)
+		switch wcRead.typ {
+		case writecacheconfig.TypeBBolt:

@@ -38,0 +51,4 @@
+		return writecacheconfig.TypeBadger
+	}
+
+	panic(fmt.Sprintf("invalid writecache type: %q", t))

@@ -39,3 +41,3 @@
 }
 
-func newCustomShard(t testing.TB, rootPath string, enableWriteCache bool, wcOpts []writecache.Option, bsOpts []blobstor.Option, metaOptions []meta.Option) *shard.Shard {
+func newCustomShard(t testing.TB, rootPath string, enableWriteCache bool, wcOpts writecacheconfig.Options, bsOpts []blobstor.Option, metaOptions []meta.Option) *shard.Shard {

@@ -0,0 +80,4 @@
+			continue
+		}
+
+		// We put objects in batches of fixed size to not interfere with main put cycle a lot.

@@ -0,0 +111,4 @@
+		check(t, mb, bs, objects)
+	})
+
+	t.Run("flush on moving to degraded mode", func(t *testing.T) {

@@ -0,0 +198,4 @@
+	return obj, data
+}
+
+func initWC(t *testing.T, wc writecache.Cache) {

@@ -0,0 +14,4 @@
+	go func() {
+		defer c.wg.Done()
+
+		t := time.NewTicker(defaultGCInterval)

@@ -0,0 +22,4 @@
+			case <-c.closeCh:
+				return
+			case <-t.C:
+				for c.db.RunValueLogGC(0.5) == nil {

@@ -0,0 +18,4 @@
+// Returns ErrNotInitialized if write-cache has not been initialized yet.
+// Returns ErrOutOfSpace if saving an object leads to WC's size overflow.
+// Returns ErrBigObject if an objects exceeds maximum object size.
+func (c *cache) Put(ctx context.Context, prm common.PutPrm) (common.PutRes, error) {

@@ -0,0 +10,4 @@
+
+func (c *cache) estimateCacheSize() uint64 {
+	onDiskSize, _ := c.db.EstimateSize(nil)
+	c.metrics.SetEstimateSize(onDiskSize, 0)

@@ -0,0 +41,4 @@
+		opts.PrefetchValues = false
+		it := tx.NewIterator(opts)
+		defer it.Close()
+		for it.Rewind(); it.Valid(); it.Next() {

@@ -0,0 +6,4 @@
+
+// OpenDB opens a badger instance for write-cache. Opens in read-only mode if ro is true.
+func OpenDB(p string, ro bool) (*badger.DB, error) {
+	return badger.Open(badger.DefaultOptions(p).WithReadOnly(ro).WithLoggingLevel(badger.ERROR))