From d0303bc8d2670d11c9df9220aa08a2c33529e100 Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Wed, 16 Jun 2021 12:34:32 +0300 Subject: [PATCH] Fix outdated comment that talked about seek position of WAL file. Since commit c24dcd0cfd, we have been using pg_pread() to read the WAL file, which doesn't change the seek position (unless we fall back to the implementation in src/port/pread.c). Update comment accordingly. Backpatch-through: 12, where we started to use pg_pread() --- src/backend/access/transam/xlog.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 17eeff0720..1b3a3d9bea 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -809,11 +809,9 @@ static XLogSegNo openLogSegNo = 0; /* * These variables are used similarly to the ones above, but for reading - * the XLOG. Note, however, that readOff generally represents the offset - * of the page just read, not the seek position of the FD itself, which - * will be just past that page. readLen indicates how much of the current - * page has been read into readBuf, and readSource indicates where we got - * the currently open file from. + * the XLOG. readOff is the offset of the page just read, readLen + * indicates how much of it has been read into readBuf, and readSource + * indicates where we got the currently open file from. * Note: we could use Reserve/ReleaseExternalFD to track consumption of * this FD too; but it doesn't currently seem worthwhile, since the XLOG is * not read by general-purpose sessions.