similar to: filefrag and btrfs filesystem defragment and maybe snapshots

Kernel 3.1-rc8 btrfs-progs-0.19 mount options: noatime,autodefrag (space_cache is enabled) There are snapshots present on the filesystem. When I do a btrfs fi defrag on a file, the file becomes much more fragmented. The end result can be a file with 20k times more fragments than before. Initially I thought the extents were just smaller but were next to each other, so I checked with both

Hi folks, I''m using Ubuntu 12.10 Quantal with # uname -r 3.5.0-24-generic And it seems I cannot defrag : # filefrag /boot/initrd.img-3.5.0-24-generic /boot/initrd.img-3.5.0-24-generic: 3 extents found # btrfs filesystem defrag /boot/initrd.img-3.5.0-24-generic # echo $? 20 # filefrag /boot/initrd.img-3.5.0-24-generic /boot/initrd.img-3.5.0-24-generic: 3 extents found Any clue

Hi all, i am new on btrfs, i am testing KVM on btrfs (host: kernel x86-64 3.5.3), the performance is reasonable. I have two question on defrag, can someone help me? 1. According to btrfs wiki, defragment a COW file will produce two unrelated files. Does it apply to the "autodefrag" mount option? 2. Is there any command for the fragmentation status of a file/dir ? e.g. fragment

Hi list, I have a few large image files (VMware workstation VMDKs and TrueCrypt containers) which I routinely back up over the network to a btrfs raid10 volume via bigsync (https://code.google.com/p/bigsync/). The VM images in particular get really fragmented due to CoW, which is expected. I haven''t yet switched off CoW on the backups directory mainly to experiment and see what

hi I have a virtualbox image of ubuntu hardy. I did filefrag and i got this hardy.vdi: 73 extents found, perfection would be 69 extents Why does it say perfection would be 69 extents. Shouldnt it be 1 extent?

Hello All, I''d like to know if there is an utility like `Filefrag'' shipped with e2fsprogs on linux, which is used to fetch the extents mapping info of a file(especially a sparse file) located on ZFS? I am working on efficient sparse file detection and backup through lseek(SEEK_DATA/SEEK_HOLE) on ZFS, and I need to verify the result by comparing the original sparse file and

Someone recently posted the following statement midway down the page at http://forums.gentoo.org/viewtopic-t-305871-postdays-0-postorder-asc-highlight-ext3+ordered+data-start-25.html >You don't need to defragment ext2/ext3 because as you use the >filesystem file blocks and inodes are moved around and reallocated >to keep the data nearly contiguous. It's not perfect, but it

Two files in the different subvolumes may have the same inode id, so The rb-tree which is used to manage the defragment object must take it into account. This patch fix this problem. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> --- fs/btrfs/file.c | 45 +++++++++++++++++++++++++++++++++++---------- 1 files changed, 35 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/file.c

The rule originally comes from nocow writing, but snapshot-aware defrag is a different case, the extent has been writen and we''re not going to change the extent but add a reference on the data. So we''re able to allow such compressed extents to be merged into one bigger extent if they''re pointing to the same data. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> ---

Hi! Today I converted my /home from Ext4 to BTRFS by reformatting and copying all over again. I created the filesystem with -l 16384 -n 16384 -d single -m single on an logical volume Intel SSD 320 and mount with compress=lzo,spacecache. Current state: merkaba:~> btrfs filesystem show failed to read /dev/sr0 Label: ''home'' uuid: […] Total devices 1 FS bytes used

I found that I''m able to provoke undefined behaviour with 2.6.38 with extent defragmenting + recompression, eg: mkfs.btrfs /dev/sdb mount /dev/sdb /mnt cp -xa / /mnt find /mnt -print0 | xargs -0 btrfs filesystem defragment -vc After a short time, I was seeing what looked like a secondary effect [1]. Reproducing with lock instrumentation reported recursive spinlock acquisition, probably

On Mon, Oct 11, 2010 at 6:46 PM, Calvin Walton <calvin.walton@gmail.com> wrote: > On Mon, 2010-10-11 at 03:30 +0300, Felipe Contreras wrote: >> I use btrfs on most of my volumes on my laptop, and I''ve always felt >> booting was very slow, but definitely sure is slow, is starting up >> Google Chrome: >> >> encrypted ext4: ~20s >> btrfs: ~2:11s

Hi, I planned to boost my btrfs performance today. here some errors I met: my ''btrfs filesystem show'' result: ~ # btrfs filesystem show failed to read /dev/sr0 Label: none uuid: 9b9aa9d9-760e-445c-a0ab-68e102d9f02e Total devices 1 FS bytes used 36.59GB devid 1 size 49.52GB used 49.52GB path /dev/sda6 Label: none uuid: 559dec06-4fd0-47c1-97b8-cc4fa6153fa0

code path: ocfs2_ioctl_move_extents ocfs2_move_extents ocfs2_defrag_extent __ocfs2_move_extent + ocfs2_journal_access_di + ocfs2_split_extent //sub-paths call jbd2_journal_restart + ocfs2_journal_dirty //crash by jbs2 ASSERT crash stacks: PID: 11297 TASK: ffff974a676dcd00 CPU: 67 COMMAND: "defragfs.ocfs2" #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01

Hello, Does anybody know how to avoid the file fragmentation when a file is created over NFSv3? A file created locally is OK: dd bs=32k if=/dev/zero of=test count=32x1024 conv=fsync filefrag test test: 10 extents found, perfection would be 9 extents When I create the file in the same dir, but from another machine, mounted over NFS: filefrag test test: 4833 extents found, perfection would be

Hi, all, I got machines running continuously for long time, but then the underlying ext3 file systems becomes quite heavily fragmented (94% non-contiguous). We just don't have a chance to shutdown the machines since they are always busy.. I tried the defrag 0.70 version comes with e2fsprog package and standalone 0.73 packages, but neither help me since the defrag tool can not handle ext3.

Wow, it takes a really long time to make a 2TB ext2fs. Are there better-than-default options that could be used for a large filesystem? mke2fs 1.34 (25-Jul-2003) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) 244203520 inodes, 488382016 blocks 24419100 blocks (5.00%) reserved for the super user First data block=0 14905 block groups 32768 blocks per group,

Hey folks, Does anybody know if any of these are on the roadmap for ZFS, or have any idea how long it''s likely to be before we see them (we''re in no rush - late 2008 would be fine with us, but it would be nice to know they''re being worked on)? I''ve seen many people ask for the ability to expand a raid-z pool by adding devices. I''m wondering if it

Hello, I habe the problems described in here https://btrfs.wiki.kernel.org/index.php/Gotchas: Files with a lot of random writes can become heavily fragmented (10000+ extents) causing trashing on HDDs and excessive multi-second spikes of CPU load on systems with an SSD or large amount a RAM. On servers and workstations this affects databases and virtual machine images. The nodatacow mount option

We''re going to use this flag EXTENT_DEFRAG to indicate which range belongs to defragment so that we can implement snapshow-aware defrag: We set the EXTENT_DEFRAG flag when dirtying the extents that need defragmented, so later on writeback thread can differentiate between normal writeback and writeback started by defragmentation. This patch is used for the latter one. Originally patch