Changing the setting of wal_sender_timeout per standby

Hello,

What do you think about changing wal_sender_timeout from PGC_HUP to PGC_BACKEND or PGC_USERSET?

Some customer wants to change the setting per standby, i.e., a shorter timeout for a standby in the same region to enable faster detection failure and failover, and a longer timeout for a standby in the remote region (for disaster recovery) to avoid mis-judging its health.

The current PGC_HUP allows to change the setting by editing postgresql.conf or ALTER SYSTEM and then sending SIGHUP to a specific walsender. But that's not easy to use. The user has to do it upon every switchover and failover.

With PGC_BACKEND, the user would be able to tune the timeout as follows:

[recovery.conf]
primary_conninfo = '... options=''-c wal_sender_timeout=60000'' ...'

With PGC_USERSET, the user would be able to use different user accounts for each standby, and tune the setting as follows:

ALTER USER repluser_remote SET wal_sender_timeout = 60000;

FYI
In Oracle Data Guard, the user configures the timeout for each standby in the primary server's configuration file like this:

LOG_ARCHIVE_DEST_1 = "SERVICE=local_conn_info SYNC NET_TIMEOUT=5"
LOG_ARCHIVE_DEST_2 = "SERVICE=remote_conn_info ASYNC NET_TIMEOUT=60"

Regards
Takayuki Tsunakawa