[pgpool-general: 1966] Re: nodes not being degenerated

[Tatsuo Ishii]

> Hi,
> 
> I have a system with two pgpools (current master code from git) and
> three database nodes.  The user manual says this:
> 
> Pgpool detected difference of the number of inserted, updated or
> deleted tuples
> 
>    In replication mode, pgpool-II detects a different number of
>    INSERT/UPDATE/DELETE rows on affected nodes.
> 
>    2010-07-22 11:49:28 ERROR: pid 30710: pgpool detected difference of
>    the number of inserted, updated or deleted tuples. Possible last query
>    was: "update t1 set i = 1;"
>    2010-07-22 11:49:28 LOG: pid 30710: ReadyForQuery: Degenerate
>    backends: 1
>    2010-07-22 11:49:28 LOG: pid 30710: ReadyForQuery: Affected tuples
>    are: 0 1
> 
>    In the example above, the returned number of updated rows by "update
>    t1 set i = 1" was different among DB nodes. The next line indicates
>    that DB 1 got degenerated (disconnected) as a consequence, and that
>    the number of affected rows for DB node 0 was 0, while for DB node 1
>    that was 1.
> 
>    Stop the DB node which is suspected of having wrong data and do an
>    online recovery.
> 
> 
> however that does not seem to be happening.  I see this in the logs
> instead:
> 
> 2013-07-31 12:33:38 ERROR: pid 30131: pgpool detected difference of
> the number of inserted, updated or deleted tuples. Possible last query
> was: " UPDATE ws_cached_searches SET status_type = $1, status_message
> = $2, processed_results = $3, truncated_results = $4, status_xml = $5
> WHERE cached_search_id = $6 and (status_type != 'ERROR' or status_type
> is null)"
> 2013-07-31 12:33:38 LOG: pid 30131: CommandComplete: Number of
> affected tuples are: 1 0 1
> 
> and node1 (in this case) stays connected.  Has this behaviour become
> broken?
> 
> Thanks,
> Sean

You need to turn on failover_if_affected_tuples_mismatch to enable the behvior.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp