Dear Fujii-san,
> > One concern for me is that the WALs might be more likely to be missed for
> > streaming replication case. What if the case walreceiver is bit busy thus send
> > buffer becomes full for a while?
> > Are there no issues because switchover after the walsender exits with FATAL is
> > not recommended?
>
> I don't think this is problematic, since PostgreSQL has never guaranteed that
> WAL data already in the send buffer will actually be delivered to the client
> at walsender FATAL exit case. But do you see this differently?
Then it might be OK. I did not recognize the policy that it's not guaranteed at FATAL.
Best regards,
Hayato Kuroda
FUJITSU LIMITED