Contents
What is the use of replication slots in Postgres?
What are PostgreSQL Replication Slots? A replication slot is a feature in PostgreSQL that ensures that the master server will retain the WAL logs that are needed by the replicas even when they are disconnected from the master.
What causes Postgres replication lag?
Causes of PostgreSQL Replication Lag Then the startup process by PostgreSQL replays the data from that WAL segment and streaming replication begins. Poor configuration in PostgreSQL such as small numbers of max_wal_senders being set while processing tons of transaction requests (or large volume of changes).
Why are PostgreSQL replication slots are necessary?
A replication slot is a feature in PostgreSQL that ensures that the master server will retain the WAL logs that are needed by the replicas even when they are disconnected from the master. This article will focus on PostgreSQL replication slots. Here is an outline of this blog: What are WAL Files? Why PostgreSQL Replication Slots are Necessary?
How does streaming replication work in PostgreSQL server?
With streaming replication, the standby server will connect to the primary server over the network (using a different protocol than the standard client protocol). The primary server can then send WAL file contents directly over this connection without having to rely on user-supplied scripts.
Do you need to restart a PostgreSQL read replica?
Starting with PostgreSQL 13, a database restart isn’t required for read replicas if the source DB instance IP address changes. For PostgreSQL versions older than 13, changes to the source DB instance IP address require a read replica reboot. IP address changes include a DB instance name change or a DB instance class change.
Can a Read Replica survive in a nonstreaming state?
A read replica can’t survive five minutes in a nonstreaming state if the source DB instance is set to the default wal_keep_segments parameter value of 32. PostgreSQL version 9.5.2 uses physical replication slots to manage write ahead log (WAL) retention on the source DB instance.