diff --git a/pkg/local_object_storage/engine/delete.go b/pkg/local_object_storage/engine/delete.go
index 47207c3b..6992bfc6 100644
--- a/pkg/local_object_storage/engine/delete.go
+++ b/pkg/local_object_storage/engine/delete.go
@@ -30,9 +30,6 @@ func (p *DeletePrm) WithAddress(addr *objectSDK.Address) *DeletePrm {
 // Returns any error encountered that did not allow to completely
 // mark the object to delete.
 func (e *StorageEngine) Delete(prm *DeletePrm) (*DeleteRes, error) {
-	e.mtx.RLock()
-	defer e.mtx.RUnlock()
-
 	shPrm := new(shard.DeletePrm)
 
 	e.iterateOverSortedShards(prm.addr, func(sh *shard.Shard) (stop bool) {
diff --git a/pkg/local_object_storage/engine/get.go b/pkg/local_object_storage/engine/get.go
index b3e5d41d..56aa2cf9 100644
--- a/pkg/local_object_storage/engine/get.go
+++ b/pkg/local_object_storage/engine/get.go
@@ -61,9 +61,6 @@ func (r *GetRes) Object() *object.Object {
 //
 // Returns ErrObjectNotFound if requested object is missing in local storage.
 func (e *StorageEngine) Get(prm *GetPrm) (*GetRes, error) {
-	e.mtx.RLock()
-	defer e.mtx.RUnlock()
-
 	var obj *object.Object
 
 	shPrm := new(shard.GetPrm).
diff --git a/pkg/local_object_storage/engine/head.go b/pkg/local_object_storage/engine/head.go
index e366cb50..153afe49 100644
--- a/pkg/local_object_storage/engine/head.go
+++ b/pkg/local_object_storage/engine/head.go
@@ -43,9 +43,6 @@ func (r *HeadRes) Header() *object.Object {
 //
 // Returns ErrObjectNotFound if requested object is missing in local storage.
 func (e *StorageEngine) Head(prm *HeadPrm) (*HeadRes, error) {
-	e.mtx.RLock()
-	defer e.mtx.RUnlock()
-
 	var head *object.Object
 
 	shPrm := new(shard.GetPrm).
diff --git a/pkg/local_object_storage/engine/put.go b/pkg/local_object_storage/engine/put.go
index 1de882a5..ff085a95 100644
--- a/pkg/local_object_storage/engine/put.go
+++ b/pkg/local_object_storage/engine/put.go
@@ -34,9 +34,6 @@ func (p *PutPrm) WithObject(obj *object.Object) *PutPrm {
 // Returns any error encountered that
 // did not allow to completely save the object.
 func (e *StorageEngine) Put(prm *PutPrm) (*PutRes, error) {
-	e.mtx.Lock()
-	defer e.mtx.Unlock()
-
 	// choose shards through sorting by weight
 	sortedShards := e.sortShardsByWeight(prm.obj.Address())
 
diff --git a/pkg/local_object_storage/engine/select.go b/pkg/local_object_storage/engine/select.go
index 289de84f..5ca1b84f 100644
--- a/pkg/local_object_storage/engine/select.go
+++ b/pkg/local_object_storage/engine/select.go
@@ -35,9 +35,6 @@ func (r *SelectRes) AddressList() []*objectSDK.Address {
 //
 // Returns any error encountered that did not allow to completely select the objects.
 func (e *StorageEngine) Select(prm *SelectPrm) (*SelectRes, error) {
-	e.mtx.RLock()
-	defer e.mtx.RUnlock()
-
 	addrList := make([]*object.Address, 0)
 
 	shPrm := new(shard.SelectPrm).
diff --git a/pkg/local_object_storage/engine/shards.go b/pkg/local_object_storage/engine/shards.go
index 3435b2c0..ee41e2d6 100644
--- a/pkg/local_object_storage/engine/shards.go
+++ b/pkg/local_object_storage/engine/shards.go
@@ -49,6 +49,9 @@ func (e *StorageEngine) shardWeight(sh *shard.Shard) float64 {
 }
 
 func (e *StorageEngine) sortShardsByWeight(objAddr fmt.Stringer) []*shard.Shard {
+	e.mtx.RLock()
+	defer e.mtx.RUnlock()
+
 	shards := make([]*shard.Shard, 0, len(e.shards))
 	weights := make([]float64, 0, len(e.shards))