//go:build linux// +build linux // Copyright (c) 2015-2021 MinIO, Inc.//// This file is part of MinIO Object Storage stack//// This program is free software: you can redistribute it and/or modify// it under the terms of the GNU Affero General Public License as published by// the Free Software Foundation, either version 3 of the License, or// (at your option) any later version.//// This program is distributed in the hope that it will be useful// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the// GNU Affero General Public License for more details.//// You should have received a copy of the GNU Affero General Public License// along with this program.  If not, see <http://www.gnu.org/licenses/>. package disk import (	"os"	"syscall" 	"golang.org/x/sys/unix") // Fdatasync - fdatasync() is similar to fsync(), but does not flush modified metadata// unless that metadata is needed in order to allow a subsequent data retrieval// to  be  correctly  handled.   For example, changes to st_atime or st_mtime// (respectively, time of last access and time of last modification; see inode(7))// do not require flushing because they are not necessary for a subsequent data// read to be handled correctly. On the other hand, a change to the file size// (st_size, as made by say ftruncate(2)), would require a metadata flush.//// The aim of fdatasync() is to reduce disk activity for applications that// do not require all metadata to be synchronized with the disk.func Fdatasync(f *os.File) error {	return syscall.Fdatasync(int(f.Fd()))} // FadviseDontNeed invalidates page-cachefunc FadviseDontNeed(f *os.File) error {	return unix.Fadvise(int(f.Fd()), 0, 0, unix.FADV_DONTNEED)}