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src/backend/access/gin/ginxlog.c

@@ -671,9 +671,10 @@ gin_redo(XLogRecPtr lsn, XLogRecord *record)
 	uint8		info = record->xl_info & ~XLR_INFO_MASK;
 
 	/*
-	 * GIN indexes do not require any conflict processing.
+	 * GIN indexes do not require any conflict processing. NB: If we ever
+	 * implement a similar optimization as we have in b-tree, and remove
+	 * killed tuples outside VACUUM, we'll need to handle that here.
 	 */
-
 	RestoreBkpBlocks(lsn, record, false);
 
 	topCtx = MemoryContextSwitchTo(opCtx);