Fix the logical replication timeout during large DDLs.

The DDLs like Refresh Materialized views that generate lots of temporary
data due to rewrite rules may not be processed by output plugins (for
example pgoutput). So, we won't send keep-alive messages for a long time
while processing such commands and that can lead the subscriber side to
timeout. We have previously fixed a similar case for large transactions in
commit f95d53eded where the output plugin filters all or most of the
changes but missed to handle the DDLs.

We decided not to backpatch this as this adds a new callback in the
existing exposed structure and moreover, users can increase the
wal_sender_timeout and wal_receiver_timeout to avoid this problem.

Author: Wang wei, Hou Zhijie
Reviewed-by: Peter Smith, Ashutosh Bapat, Shi yu, Amit Kapila
Discussion: https://postgr.es/m/OS3PR01MB6275478E5D29E4A563302D3D9E2B9@OS3PR01MB6275.jpnprd01.prod.outlook.com
Discussion: https://postgr.es/m/CAA5-nLARN7-3SLU_QUxfy510pmrYK6JJb=bk3hcgemAM_pAv+w@mail.gmail.com

1 files changed, 12 insertions, 0 deletions

diff --git a/src/include/replication/reorderbuffer.h b/src/include/replication/reorderbuffer.h
index e5db041df18..215d1494e90 100644
--- a/src/include/replication/reorderbuffer.h
+++ b/src/include/replication/reorderbuffer.h
@@ -526,6 +526,12 @@ typedef void (*ReorderBufferStreamTruncateCB) (
 											   Relation relations[],
 											   ReorderBufferChange *change);
 
+/* update progress txn callback signature */
+typedef void (*ReorderBufferUpdateProgressTxnCB) (
+												  ReorderBuffer *rb,
+												  ReorderBufferTXN *txn,
+												  XLogRecPtr lsn);
+
 struct ReorderBuffer
 {
 	/*
@@ -590,6 +596,12 @@ struct ReorderBuffer
 	ReorderBufferStreamTruncateCB stream_truncate;
 
 	/*
+	 * Callback to be called when updating progress during sending data of a
+	 * transaction (and its subtransactions) to the output plugin.
+	 */
+	ReorderBufferUpdateProgressTxnCB update_progress_txn;
+
+	/*
 	 * Pointer that will be passed untouched to the callbacks.
 	 */
 	void	   *private_data;