Hello, Use xfs_io to test preallocate. It returns successfuly. But it's a empty file. And doesn't allocate space. # mount //localhost/cifs ~/cifs # xfs_io -f -c "resvsp 4 4" cifs/file # du -h cifs/file 0 cifs/file Test on xfs: # rm -rf file # xfs_io -f -c "resvsp 4 4" file # du -h file 4.0K file Is it expected for cifs? I think the size should be a block size(1M for cifs). Thanks. -- Best regards! XiaoLi Feng 冯小丽 Red Hat Software (Beijing) Co.,Ltd filesystem-qe Team IRC:xifeng，#channel: fs-qe Tel:+86-10-8388112 9/F, Raycom
