1 files changed, 6 insertions, 0 deletions
diff --git a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
index 7f57527367e..3cb23e4e565 100644
--- a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
+++ b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
@@ -635,6 +635,12 @@ private:
 
     void _enqueueRequest(WithLock, RequestData&& request);
 
+    /**
+     * Clears any persisted state and releases any distributed lock associated to the list of
+     * requests specified.
+     * This method must not be called while holding any mutex (this could cause deadlocks if a
+     * stepdown request is also being served).
+     */
     void _performDeferredCleanup(
         OperationContext* opCtx,
         const stdx::unordered_map<UUID, RequestData, UUID::Hash>& requestsHoldingResources);