From: Kyotaro HORIGUCHI [mailto:horiguchi.kyot...@lab.ntt.co.jp] > At Fri, 14 Sep 2018 18:22:33 +0900, Masahiko Sawada <sawada.m...@gmail.com> > wrote in > <CAD21AoBr2Y=n4ih8+6m5ara2gwdke6zrzwaqjzux6erz9py...@mail.gmail.com> > > 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. > > +1, and we need a means to see the actual value, in > pg_stat_replication?
Thanks, the patch attached. I'll add this to the next CF shortly. As Michael said, I think viewing the configured value would be a separate feature. Regards Takayuki Tsunakawa
walsender_timeout_PGC_BACKEND.patch
Description: walsender_timeout_PGC_BACKEND.patch
