> But, I heard PgPool is still affected by Split brain syndrome. Can you elaborate more? If more than 3 pgpool watchdog nodes (the number of nodes must be odd) are configured, a split brain can be avoided. Best reagards, -- Tatsuo Ishii SRA OSS LLC English: http://www.sraoss.co.jp/index_en/ Japanese:http://www.sraoss.co.jp > Regards, > > Inzamam Shafiq > Sr. DBA > ________________________________ > From: Tatsuo Ishii <ishii@xxxxxxxxxxxx> > Sent: Wednesday, April 5, 2023 12:38 PM > To: cyberdemn@xxxxxxxxx <cyberdemn@xxxxxxxxx> > Cc: inzamam.shafiq@xxxxxxxxxxx <inzamam.shafiq@xxxxxxxxxxx>; pgsql-general@xxxxxxxxxxxxxxxxxxxx <pgsql-general@xxxxxxxxxxxxxxxxxxxx> > Subject: Re: Patroni vs pgpool II > >> BUT, even if there is a solution that parses queries to make a decision it >> I would not recommend anyone to use it unless all consequences are >> understood. >> Specifically, not every read-only query could be salefy sent to a replica, >> because they could be lagging behind the primary. >> Only application (developers) could decide whether for a specific query >> they could afford slightly outdated results. Most of the popular >> application frameworks support configuring two connection strings for this >> purpose. > > I think Pgpool-II users well understand the effect of replication > lagging because I've never heard complains like "hey, why my query > result is sometimes outdated?" > > Moreover Pgpool-II provides many load balancing features depending on > user's needs. For example users can: > > - just turn off load balancing > - turn off load balancing only for specific application name > - turn off load balancing only for specific database > - turn off load balancing if current transaction includes write query > > Best reagards, > -- > Tatsuo Ishii > SRA OSS LLC > English: http://www.sraoss.co.jp/index_en/ > Japanese:http://www.sraoss.co.jp
