Simon Riggs wrote:
> 2. Master ignores Standby's OldestXmin
> Effects:
> * Long running queries on standby...
> Have no effect on primary
> Can delay apply of WAL records on standby
> * Queries on standby give consistent answers in all cases.
Just for clarification, if you set a max_slave_delay it means it is the
maximum amount of time WAL replay can be delayed on the slave, _and_ it
is the maximum amount of time a query/snapshot can be guaranteed to run
without the possibility of being canceled. My point is that these two
concepts are linked to the same setting.
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +