PostgreSQL ERROR: canceling statement due to conflict with recovery

Question

I\'m getting the following error when running a query on a PostgreSQL db in standby mode. The query that causes the error works fine for 1 month but when you query for more

Answer 1

There's no need to start idle transactions on the master. In postgresql-9.1 the most direct way to solve this problem is by setting

hot_standby_feedback = on

This will make the master aware of long-running queries. From the docs:

The first option is to set the parameter hot_standby_feedback, which prevents VACUUM from removing recently-dead rows and so cleanup conflicts do not occur.

Why isn't this the default? This parameter was added after the initial implementation and it's the only way that a standby can affect a master.