diff --git a/src/Storages/StorageTinyLog.cpp b/src/Storages/StorageTinyLog.cpp
index 3cb4be50a8651e8bae71978d5bbff3ffb6446c8a..6ce41dac614a87780d77b76ca3ffea1f2193b251 100644
--- a/src/Storages/StorageTinyLog.cpp
+++ b/src/Storages/StorageTinyLog.cpp
@@ -357,6 +357,8 @@ void TinyLogBlockOutputStream::writeSuffix()
     for (const auto & file : column_files)
         storage.file_checker.update(file);
     storage.file_checker.save();
+
+    lock.unlock();
 }
 
 
diff --git a/src/Storages/StorageTinyLog.h b/src/Storages/StorageTinyLog.h
index b76e8e34dfb8bbfb818a85871405e11be5da113f..1187f7f905d708b2636d9a72f2e3592d013c904c 100644
--- a/src/Storages/StorageTinyLog.h
+++ b/src/Storages/StorageTinyLog.h
@@ -70,7 +70,7 @@ private:
     Files files;
 
     FileChecker file_checker;
-    mutable std::shared_timed_mutex rwlock;
+    std::shared_timed_mutex rwlock;
 
     Poco::Logger * log;