From 3bdbdf5d06f2179d4c17926d77ff734ea9e7d525 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Tue, 8 Nov 2022 12:23:46 +0900 Subject: Introduce pg_pwrite_zeros() in fileutils.c This routine is designed to write zeros to a file using vectored I/O, for a size given by its caller, being useful when it comes to initializing a file with a final size already known. XLogFileInitInternal() in xlog.c is changed to use this new routine when initializing WAL segments with zeros (wal_init_zero enabled). Note that the aligned buffers used for the vectored I/O writes have a size of XLOG_BLCKSZ, and not BLCKSZ anymore, as pg_pwrite_zeros() relies on PGAlignedBlock while xlog.c originally used PGAlignedXLogBlock. This routine will be used in a follow-up patch to do the pre-padding of WAL segments for pg_receivewal and pg_basebackup when these are not compressed. Author: Bharath Rupireddy Reviewed-by: Nathan Bossart, Andres Freund, Thomas Munro, Michael Paquier Discussion: https://www.postgresql.org/message-id/CALj2ACUq7nAb7%3DbJNbK3yYmp-SZhJcXFR_pLk8un6XgDzDF3OA%40mail.gmail.com --- src/include/common/file_utils.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'src/include/common/file_utils.h') diff --git a/src/include/common/file_utils.h b/src/include/common/file_utils.h index 2c5dbcb0b1e..d2c64c2196c 100644 --- a/src/include/common/file_utils.h +++ b/src/include/common/file_utils.h @@ -44,4 +44,6 @@ extern ssize_t pg_pwritev_with_retry(int fd, int iovcnt, off_t offset); +extern ssize_t pg_pwrite_zeros(int fd, size_t size); + #endif /* FILE_UTILS_H */ -- cgit v1.2.3