All, I've been playing with vacuum_defer_cleanup_age in reference to the query cancel problem. It really seems to me that this is the way forward in terms of dealing with query cancel for normal operation rather than wal_standby_delay, or maybe in combination with it.
As a first test, I set up a deliberately pathological situation with pgbench and a wal_standby_delay of 1 second. This allowed me to trigger query cancel on a relatively simple reporting query; in fact, to make it impossible to complete. Then I increased vacuum_defer_cleanup_age to 100000, which represents about 5 minutes of transactions on the test system. This eliminated all query cancels for the reporting query, which takes an average of 10s. Next is a database bloat test, but I'll need to do that on a system with more free space than my laptop. --Josh Berkus -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
