使用mongo驱动程序的MongoDB事务

bool
create_and_insert_doc (mongoc_client_session_t *session,
                       void *ctx,
                       bson_t **reply, /* out param for our server reply */
                       bson_error_t *error)
{
   /*
    * mongoc_collection_insert_one requires an uninitialized, stack-allocated
    * bson_t to receive the update result
    */
   bson_t local_reply;
   bson_t *doc = NULL;
   ctx_t *data = NULL;
   bool retval;


   for (int i = 0; i < 1000; i++) {
      doc = BCON_NEW ("new", BCON_INT32 (2), "val", BCON_INT32 (2));
      printf ("Running the user-defined callback in a newly created transaction...\n");
      data = (ctx_t *) ctx;
      retval = mongoc_collection_insert_one (data->collection, doc, data->insert_opts, &local_reply, error);
      {
         sleep(0.5);
      }  
   }
   printf ("sleep end...\n");
   /*
    * To return to the mongoc_client_session_with_transaction() method, set
    * *reply to a new copy of our local_reply before destroying it.
    */
   *reply = bson_copy (&local_reply);
   bson_destroy (&local_reply);

   bson_destroy (doc);
   return retval;
}

mongoc_client_session_with_transaction (session, &create_and_insert_doc, NULL, &ctx, &reply, &error);

当我使用上面的mongoc驱动程序进行Transaction并运行代码时,它仅插入文档就运行了大约5秒。 插入、更新、创建索引等其他操作不会被阻止。为什么?

我知道mongodb使用意向锁、共享锁、独占锁。因此,如果我进行的事务只插入单个文档,则会为数据库和集合获得一个意向独占锁,为文档获得一个独占锁。

我想我错过或误解了什么。感谢阅读。

我运行了测试代码,检查了db.currentOp(),在运行事务时运行了insert、update、create index。