On Mon, Oct 19, 2009 at 3:17 PM, Prasad Joshi <prasadjoshi...@gmail.com> wrote: > On Mon, Oct 19, 2009 at 7:56 AM, Yan, Zheng <yanzh...@21cn.com> wrote: >> On Sun, Oct 18, 2009 at 10:35 PM, Prasad Joshi <prasadjoshi...@gmail.com> >> wrote: >>> Hi, >>> >>> I tried using the btrfs-convert utility to convert the ext2 fs to >>> btrfs. After the conversion was over, just to verify the correctness >>> of operation, ran btrfsck on the device. It showed errors 800. I am >>> not sure what does it mean, so thought of repoting it on mailing list. >>> >>> # btrfsck /dev/sdb >>> root 256 inode 257 errors 800 >>> found 1105965056 bytes used err is 1 >>> total csum bytes: 192576 >>> total tree bytes: 459956224 >>> total fs tree bytes: 449585152 >>> btree space waste bytes: 191448023 >>> file data blocks allocated: 843206656 >>> referenced 843206656 >>> Btrfs v0.19-3-g6f3cf25-dirty >> >> "root 256 inode 257" is the ext2 image file. Checksum for file extents in >> the ext2 image file is very special, so btrfsck treat it as error. This error >> has no harm, it will go away after deleting the ext2 image file. > OKay thanks. >> >>> >>> I also found that, after the conversion of FS from ext2 to btrfs >>> %usage gone up drastically. I mean before the conversion ext2 FS was >>> 22% full but then converted btrfs is 64% used. >>> >>> Steps Followed >>> =========== >>> 1. Created an ext2 filesystem of size 2G >>> 2. Created about 178 files of size 1M in a directory. FS was 11% full >>> after the operation. >>> 3. In another directory create near about 1 Lac files of very small >>> size (2K). I kept on creating files till the number of available >>> inodes were exhausted. >>> >>> # fsck /dev/sdb >>> fsck 1.41.3 (12-Oct-2008) >>> e2fsck 1.41.3 (12-Oct-2008) >>> /dev/sdb: clean, 131072/131072 files, 188721/524288 blocks >>> >>> At this point df -kh output showed that FS as 22% full >>> >>> 4. Tried to convert the ext2 FS to btrfs using btrfs-convert utility >>> >>> # btrfs-convert /dev/sdb >>> creating btrfs metadata. >>> creating ext2fs image file. >>> cleaning up system chunk. >>> conversion complete. >>> >>> 5. Ran btrfsck. >>> >>> 6. Mounted the file system >>> >>> # df -kh >>> Filesystem Size Used Avail Use% Mounted on >>> .... >>> .... >>> tmpfs 251M 104K 251M 1% /dev/shm >>> /dev/sdb 2.0G 1.3G 740M 64% /mnt/fs >>> >>> As you can see df displays FS is 64% full, when infact before >>> conversion it was onlly 22% full. Why is so much increase in >>> percentage usage? >> >> This is a accounting bug, it's already fixed in btrfs-progs-unstable tree.. > I am using the latest btrfs-progs-unstable tree. I had cloned the git > repository, I used the same updated repository. Is there any other > repository than the one declared on Wiki Page? > I used cloned repo from > git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs-unstable.git
It's not accounting bug. I guess it's due to small file packing. Please try using -n option. Yan, Zheng -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
