Heartbeat between Primary and Standby replicas

Hello everyone,<br /><br />I am designing a heartbeat system between replicas to know when a replica goes down so that
necessarymeasures can be taken. As I see, there are two ways of doing it:<br /><br />1) Creating a separate heartbeat
processon replicas.<br /> 2) Creating a heartbeat message, and sending it over the connection that is already
establishedbetween walsender and walreceiver.<br /><br />With 2, sending heartbeat from walsender to walreceiver seems
trivial.Sending a heartbeat from walreceiver to walsender seems tricky. Going through the code, it seems that the
walreceiveris always in the PGASYNC_COPY_OUT mode (except in the beginning when handshaking is done).<br /><br />Can
yourecommend the right way of doing this?<br /><br />Thank you.<br /><br />Regards<br /><br
/>---------------------------<br/>Postgres version = 9.0 beta-4<br />