The allowed values are
immediate. The default is
buffered. This parameter is intended to be used to test logical decoding and replication of large transactions. The effect of
debug_logical_replication_streaming is different for the publisher and subscriber:
On the publisher side,
debug_logical_replication_streaming allows streaming or serializing changes immediately in logical decoding. When set to
immediate, stream each change if the option of is enabled, otherwise, serialize each change. When set to
buffered, the decoding will stream or serialize changes when logical_decoding_work_mem is reached.
On the subscriber side, if the
streaming option is set to
debug_logical_replication_streaming can be used to direct the leader apply worker to send changes to the shared memory queue or to serialize all changes to the file. When set to
buffered, the leader sends changes to parallel apply workers via a shared memory queue. When set to
immediate, the leader serializes all changes to files and notifies the parallel apply workers to read and apply them at the end of the transaction.