diff --git a/sql/handler.cc b/sql/handler.cc
index d2eaab19ad8..20bf2355c25 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -2397,6 +2397,17 @@ int handler::update_auto_increment()
         reservation means potentially losing unused values).
         Note that in prelocked mode no estimation is given.
       */
+
+      /*
+        For multi-row inserts, if the bulk inserts cannot be started, the
+        handler::estimation_rows_to_insert will not be set. Set it here.
+      */
+      if ((estimation_rows_to_insert == 0) &&
+          (thd->lex->many_values.elements > 0))
+      {
+        estimation_rows_to_insert= thd->lex->many_values.elements;
+      }
+
       if ((auto_inc_intervals_count == 0) && (estimation_rows_to_insert > 0))
         nb_desired_values= estimation_rows_to_insert;
       else /* go with the increasing defaults */
@@ -4690,6 +4701,8 @@ int handler::ha_write_row(uchar *buf)
     DBUG_RETURN(error);
   if (unlikely(error= binlog_log_row(table, 0, buf, log_func)))
     DBUG_RETURN(error); /* purecov: inspected */
+
+  DEBUG_SYNC_C("ha_write_row_end");
   DBUG_RETURN(0);
 }