On Thu, Sep 13, 2018 at 12:32 PM, Michael Paquier <mich...@paquier.xyz> wrote: > On Thu, Sep 13, 2018 at 01:14:12AM +0000, Tsunakawa, Takayuki wrote: >> 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. > > This argument is sensible. > >> 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; > > It seems to me that switching to PGC_BACKENDwould cover already all the > use-cases you are mentioning, as at the end one would just want to > adjust the WAL sender timeout on a connection basis depending on the > geographical location of the receiver and the latency between primary > and standby.
+1 for PGC_BACKEND. It looks enough for most use cases. Regards, -- Masahiko Sawada NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center
