No, I don't have any snapshots or subvolumes. Only that single file. The file has both checksums and datacow on it. I will do "chattr +C" on the parent dir and re-create the file to make sure all files are marked as "nodatacow". Should I also turn off checksums with the mount-flags if this filesystem only contain big VM-files? Or is it not needed if I put +C on the parent dir? 2014-12-20 2:53 GMT+08:00 Phillip Susi <psusi@xxxxxxxxxx>: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 12/18/2014 9:59 AM, Daniele Testa wrote: >> As seen above, I have a 410GB SSD mounted at "/opt/drives/ssd". On >> that partition, I have one single starse file, taking 302GB of >> space (max 315GB). The snapshots directory is completely empty. > > So you don't have any snapshots or other subvolumes? > >> However, for some weird reason, btrfs seems to think it takes >> 404GB. The big file is a disk that I use in a virtual server and >> when I write stuff inside that virtual server, the disk-usage of >> the btrfs partition on the host keeps increasing even if the >> sparse-file is constant at 302GB. I even have 100GB of "free" >> disk-space inside that virtual disk-file. Writing 1GB inside the >> virtual disk-file seems to increase the usage about 4-5GB on the >> "outside". > > Did you flag the file as nodatacow? > >> Does anyone have a clue on what is going on? How can the >> difference and behaviour be like this when I just have one single >> file? Is it also normal to have 672MB of metadata for a single >> file? > > You probably have the data checksums enabled and that isn't > unreasonable for checksums on 302g of data. > > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v2.0.17 (MingW32) > > iQEcBAEBAgAGBQJUlHQyAAoJENRVrw2cjl5RZWEIAKfdDzlNVrD/IYDZ5wzIeg5P > DR5H8anGGc2QPTAD76vEX/XA7/j1Kg+PbQRHGdz6Iq2+Vq4CGno/yIi46oVVVYaL > H4XvuH7GvPJyzHJ+XCMHjPGLrSCBxgIm1XSluNXmFNCwqi/FONk8TUhWsw7JchaZ > yCVe/82YI+MLZhmJdudt48MeNFzW6LYi58dQo/JfYnTGnpZAFutdgBM7vLmnqLY2 > WVLQUNHZsHBa7solttCuRtc4h8ku9FBObfKKYNPAEn1YWfx7bihWgPeBMH/blsza > yhpMq96OMhIfn2SmIZMSwGh2ys+AxQQfymYR69fyGYTIajHmJEhJUzltuQD9Yg8= > =Z9/S > -----END PGP SIGNATURE----- -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
