31.8. Configuration Settings
Logical replication requires several configuration options to be set.
On the publisher side,
wal_level
must be set to
logical
, and
max_replication_slots
must be set to at least the number of subscriptions expected to connect,
plus some reserve for table synchronization. And
max_wal_senders
should be set to at least the same as
max_replication_slots
plus the number of physical
replicas that are connected at the same time.
max_replication_slots
must also be set on the subscriber.
It should be set to at least the number of subscriptions that will be added
to the subscriber, plus some reserve for table synchronization.
max_logical_replication_workers
must be set to at least
the number of subscriptions, again plus some reserve for the table
synchronization. Additionally the
max_worker_processes
may need to be adjusted to accommodate for replication workers, at least
(
max_logical_replication_workers
+
1
). Note that some extensions and parallel queries
also take worker slots from
max_worker_processes
.