diff --git a/src/StorageCache.cpp b/src/StorageCache.cpp
index 29908c7f5..e33c97ff7 100644
--- a/src/StorageCache.cpp
+++ b/src/StorageCache.cpp
@@ -140,5 +140,6 @@ size_t StorageCache::count() const
 
 void StorageCache::beginWriteBatch() { 
     serverAssert(GlobalLocksAcquired());    // Otherwise we deadlock
+    m_lock.lock();
     m_spstorage->beginWriteBatch(); 
 }
\ No newline at end of file