memory leak

[18328594608]

template <typename connection, typename config>
void endpoint<connection,config>::send(connection_hdl hdl, std::string const & payload,
frame::opcode::value op)
{
lib::error_code ec;
send(hdl,payload,op,ec);
if (ec) { throw exception(ec); }
}

__m_websocktServer.send(spMsg->getWebsocketHdl(),msg, websocketpp::frame::opcode::value::text);

The functions and methods used are as above
The current behavior is that during the program run, the send function is repeatedly called, and msg is not empty. The memory is continuously reduced as the call time becomes. If there is a lot of content in msg, the memory will be reduced faster