Clear up btree_xlog_split() alignment comment.
Adjust a comment that describes how alignment of the new left page high
key works in btree_xlog_split(), the nbtree page split REDO routine.
The wording used before commit is much clearer, so go back
to that.
@@ -281,7 +281,11 @@ btree_xlog_split(bool onleft, XLogReaderState *record)
datalen -= newitemsz;
}
- /* Extract left hikey and its size (assuming 16-bit alignment) */
+ /*
+ * Extract left hikey and its size. We assume that 16-bit alignment
+ * is enough to apply IndexTupleSize (since it's fetching from a
+ * uint16 field).
+ */
left_hikey = (IndexTuple) datapos;
left_hikeysz = MAXALIGN(IndexTupleSize(left_hikey));
datapos += left_hikeysz;
