@@ -397,4 +432,2 @@
 }
 
-// PutStream puts executes handler on a file opened for write.
-func (t *FSTree) PutStream(addr oid.Address, handler func(*os.File) error) error {

@@ -74,6 +74,7 @@ func (c *cache) Put(ctx context.Context, prm common.PutPrm) (common.PutRes, erro
 	if err == nil {
 		added = true
 	}
+	c.estimateCacheSize()

@@ -58,3 +60,4 @@
 	if err := c.fsTree.Open(readOnly); err != nil {
 		return fmt.Errorf("could not open FSTree: %w", err)
 	}
+	if err := c.fsTree.Init(); err != nil {

@@ -67,2 +74,3 @@
 		b := tx.Bucket(defaultBucket)
-		return b.Delete([]byte(key))
+		key := []byte(key)
+		recordDeleted = !recordDeleted && b.Get(key) != nil

@@ -371,0 +397,4 @@
+		t.counter.Inc()
+		var targetFileExists bool
+		if _, e := os.Stat(p); e == nil {
+			targetFileExists = true

@@ -97,2 +100,3 @@
 		)
-		c.objCounters.IncDB()
+		if recordAdded {
+			c.objCounters.cDB.Add(1)

@@ -15,1 +13,3 @@
-	return db + fstree
+	dbCount := c.objCounters.DB()
+	fsCount := c.objCounters.FS()
+	if fsCount > 0 {

@@ -364,10 +394,21 @@ func (t *FSTree) writeAndRename(tmpPath, p string, data []byte) error {
 			case syscall.ENOSPC:
 				err = common.ErrNoSpace
 				_ = os.RemoveAll(tmpPath)
-			case syscall.EEXIST:

@@ -89,2 +90,3 @@
 		b := tx.Bucket(defaultBucket)
-		return b.Put([]byte(obj.addr), obj.data)
+		key := []byte(obj.addr)
+		recordAdded = !recordAdded && b.Get(key) == nil

@@ -351,3 +370,2 @@
 
-	err = fmt.Errorf("couldn't read file after %d retries", retryCount)
-	// unreachable, but precaution never hurts, especially 1 day before release.
+	tmpPath := p + "#" + uuid.NewString()

@@ -0,0 +17,4 @@
+func (c *noopCounter) Inc()       {}
+func (c *noopCounter) Dec()       {}
+
+type SimpleCounter struct {

@@ -528,7 +534,6 @@ func (t *FSTree) NumberOfObjects() (uint64, error) {
 	if err != nil {
 		return 0, fmt.Errorf("could not walk through %s directory: %w", t.RootPath, err)
 	}
-

@@ -351,3 +348,1 @@
-
-	err = fmt.Errorf("couldn't read file after %d retries", retryCount)
-	// unreachable, but precaution never hurts, especially 1 day before release.
+	tmpPath := p + "#" + uuid.NewString()

@@ -371,0 +378,4 @@
+		}
+		err = os.Rename(tmpPath, p)
+		if err == nil && targetFileExists {
+			t.counter.Dec() //target already exists, tmp file removed, so no counter changes

@@ -72,4 +74,1 @@
-		inFS-- //small.bolt DB file
-	}
-
 	c.objCounters.cDB.Store(inDB)