Improve description of buffer used to store records in WAL reader

The dedicated private buffer to store records is used only for these
crossing a page boundary since 285bd0ac, but its description did not
match completely the reality.

Reported-by: Andrey Lepikhov
Author: Michael Paquier
Discussion: https://postgr.es/m/49518b48-2036-5e43-1818-0f594e375e76@postgrespro.ru

diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h
index 40116f8ecb4a813b82a8020004a4d97c16a381c4..44ca2bc2fdae20221d9aa31683fa212f7f046fcb 100644 (file)
--- a/src/include/access/xlogreader.h
+++ b/src/include/access/xlogreader.h
@@ -185,7 +185,10 @@ struct XLogReaderState
     */
    TimeLineID  nextTLI;
 
-   /* Buffer for current ReadRecord result (expandable) */
+   /*
+    * Buffer for current ReadRecord result (expandable), used when a record
+    * crosses a page boundary.
+    */
    char       *readRecordBuf;
    uint32      readRecordBufSize;