[pgpool-general: 5061] Re: Possible bug in streaming replication/load-balancing mode when standby is up but way behind.

[Tatsuo Ishii]

> In two cases, I've gotten this error from PGPool 3.5.4 (with PostgreSQL 9.5.4) when a hot standby was up and available, but not replicating properly and way behind the primary:
> 
> -bash-4.1$ psql -h localhost -U jiralt01 jiralt01
> psql: ERROR: unable to read message kind
> DETAIL: kind does not match between master(53) slot[1] (45)
> -bash-4.1$

Do you know how to reproduce the problem?  Just creating an excess
replication delay does not reproduce the problem here.

> What I believe should happen is that PGPool should detach that standby (delay_threshold = 10000000)...instead it blocks anything from connecting, which does NOT lead to the intended high-availability of this SR+LB configuration.

Sounds an idea but it will break existing behavior. Should be proposed
as a new feature (e.g. requires new switch).

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp