Logical replication requires several configuration options to be set.
On the publisher side,
must be set to
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
max_replication_slots plus the
number of physical replicas that are connected at the same
The subscriber also requires the
max_replication_slots to be set. In this case it
should be set to at least the number of subscriptions that will be
added to the subscriber.
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 (
1). Note that some extensions and parallel queries
also take worker slots from
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.