[pgpool-general: 1622] Re: inserts sent to standby

[Tatsuo Ishii]

> I have been running pgpool 3.2.3 in production and everything has been working great.  However, I recently had an incident where pgpool started sending inserts to the the read-only standby and not the master.  I'm using master/slave mode with streaming replication and both the master and slave were up and running and when I checked the pgpool status, everything seemed normal.  I'm also using delay_threshold = 100000.  When this incident occurred, it was after a large data update in which the lag exceed this threshold.  I believe that once the threshold was no longer exceeded, it started sending queries back to the standby and also started sending inserts there too.
> 
> Am I understanding this feature correctly?  If the lag exceeds the delay_threshold, it stops sending queries to the standby and when it drops below the threshold, it resumes.  Any idea as to why it would send inserts to the standby?  I did not have debug on, so I don't have much information to go on, except I do know that the delay_threshold was exceeded and shortly after it was no longer exceeded, this started happening.  Restarting pgpool cleared it up.

Your understanding of delay_threshold behavior is correct and sounds
like the incident you observed is a bug. I will try to reproduce the
problem to find out what is wrong.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp