‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tue, 2021-07-13 at 20:14 -0700, David G. Johnston wrote:
On Tue, Jul 13, 2021 at 8:01 PM Lucas root@sud0.nz wrote:
According to the documentation, max_standby_streaming_delay is a configuration parameter
determining how long a standby server should wait before canceling queries that conflict
with pending WAL entries received via streaming replication.
My question then is: Which queries, if the slave can only receive SELECTs?
The select queries...
Follow the link in the docs for max_stanbdy_steaming_delay to:
https://www.postgresql.org/docs/current/hot-standby.html#HOT-STANDBY-CONFLICT
for the details.
Perhaps you might find the following article interesting, where I tried to
discuss this topic in some depth:
https://www.cybertec-postgresql.com/en/streaming-replication-conflicts-in-postgresql/
Thanks!
I have changed max_standby_streaming_delay from -1 to 120s. However, I can still see the replication being delayed for up to 3 minutes quite frequent.
I will try to see if I can find what kind of query is causing that... Maybe via pg_stat_database_conflicts?
