similar to: Re: [systemd-devel] systemd-udevd: excessive I/O usage

I''ve been monitoring the lists for a while now but didn''t see this problem mentioned in particular: I''ve got a fairly standard desktop system at home, 700gb WD drive, nothing special, with 2 btrfs filesystems and some snapshots. The system runs for days, and I''ve noticed unusual disk activity the other evening - turns out that it''s taking forever to

Hi, I have 4 machines, all converted to BTRFS about 6 months ago, now all running Ubuntu Quantal with kernel 3.5.0-17 The matter is that all these machines are now getting slower and slower everyday, every disk access causing the disk to be 100% busy for long periods, to the point that I''m now seriously considering migrating everything back to ext4... From the start BTRFS was "not

Hi, I have added 2x2Tb to my existing 2x2Tb raid 1 btrfs filesystem and then ran a balance: # btrfs filesystem show Total devices 4 FS bytes used 1.74TB devid 3 size 1.82TB used 0.00 path /dev/sdd devid 4 size 1.82TB used 0.00 path /dev/sde devid 2 size 1.82TB used 1.75TB path /dev/sdc devid 1 size 1.82TB used 1.75TB path /dev/sdb # btrfs

Hi, Recently, I made a btrfs to use. And I met slowness problem. Trying to diag it. I found this: 1. dd if=/dev/zero of=test count=1024 bs=1MB This is fast, at about 25MB/s, and reasonable iowait. 2. dd if=/dev/zero of=test count=1 bs=1GB This is pretty slow, at about 1.5MB/s, and 90%+ iowait, constantly. May I know why it works like this? Thanks. -- To unsubscribe from this list: send the

In btrfs if we mount with "compress" we have no way to disable compressing by remounting (mount -o remount /mnt/btrfs), only by unmounting and mounting without "compress". This patch adds "nocompress" mount option which can be used to remount the filesystem without compression: # mount -o remount,nocompress /mnt/btrfs This option is usefull in cases when we have a

Hi, We have file readahead to do asyn file read, but has no metadata readahead. For a list of files, their metadata is stored in fragmented disk space and metadata read is a sync operation, which impacts the efficiency of readahead much. The patches try to add meatadata readahead for btrfs. In btrfs, metadata is stored in btree_inode. Ideally, if we could hook the inode to a fd so we could use

This was a request from the systemd guys. They need a quick and easy way to get all devices attached to a Btrfs filesystem in order to check if any of the disks are SSD for...something, I didn''t ask :). I''ve tested this with the btrfs-progs patch that accompanies this patch. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> --- fs/btrfs/ioctl.c | 64

Hi, using btrfs with LVM snapshots seems to be confusing /proc/mounts After mounting a snapshot of an original filesystem, the devicename of the original filesystem is overwritten with that of the snapshot in /proc/mounts. Steps to reproduce: arnd@kallisto:/mnt$ sudo mount /dev/vg0/original /mnt/original [ 107.041432] device fsid 5c3e8ca2-da56-4ade-9fef-103a6a8a70c2 devid 1 transid 4

Hello! I''m using ArchLinux with kernel Linux horus 3.10.5-1-ARCH #1 SMP PREEMPT. Mounting and unmounting takes a long time: # time mount -v /mnt/Archiv mount: /dev/sde1 mounted on /mnt/Archiv. mount -v /mnt/Archiv 0,00s user 0,16s system 1% cpu 9,493 total # sync && time umount -v /mnt/Archiv umount: /mnt/Archiv (/dev/sdd1) unmounted umount -v /mnt/Archiv 0,00s user

When adding orphans to an inode''s root, we start a transaction for that root that when ended in several places such as for example extent-tree.c:btrfs_remove_block_group(), inode.c:btrfs_unlink() and inode.c:btrfs_evict_node(), doesn''t result in a commit, that is, inode.c:btrfs_orphan_commit_root() doesn''t get called (via transaction.c:commit_fs_roots()). The respective

I set the C (NOCOW) and z (Not_Compressed) flags on a folder but the extent counts of files contained there keep increasing. Said files are large and frequently modified but not changing in size. This does not happen when the filesystem is mounted with nodatacow. I''m using this as a workaround since subvolumes can''t be mounted with different options simultaneously. ie. one with

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

This series introduces a generic readahead interface for btrfs trees. The intention is to use it to speed up scrub in a first run, but balance is another hot candidate. In general, every tree walk could be accompanied by a readahead. Deletion of large files comes to mind, where the fetching of the csums takes most of the time. Also the initial build-ups of free-space-caches and

This series introduces a generic readahead interface for btrfs trees. The intention is to use it to speed up scrub in a first run, but balance is another hot candidate. In general, every tree walk could be accompanied by a readahead. Deletion of large files comes to mind, where the fetching of the csums takes most of the time. Also the initial build-ups of free-space-caches and

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

Hello Hendrik Can you help input 2 commands 'mount' and 'df -TPh' on OMV, and post the output to us, thank you. -- Regards, Jones Syue | ??? QNAP Systems, Inc.

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

From: Raghavendra D Prabhu <rprabhu@wnohang.net> From 51daa88ebd8e0d437289f589af29d4b39379ea76, page_sync_readahead coalesces async readahead into its readahead window, so another checking for that again is not required. Signed-off-by: Raghavendra D Prabhu <rprabhu@wnohang.net> --- fs/btrfs/relocation.c | 10 ++++------ mm/filemap.c | 3 +-- 2 files changed, 5

If we have particularly full nodes, we could call btrfs_node_blockptr up to 32 times, which is 32 pairs of kmap/kunmap, which _sucks_. So go ahead and map the extent buffer while we look for readahead targets. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> --- fs/btrfs/ctree.c | 23 +++++++++++++++++++++-- 1 files changed, 21 insertions(+), 2 deletions(-) diff --git

Dear list members, In my previous thread at http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg23333.html there was a space_cache kernel bug/panic on kernel 3.8. I could successfully "fix" that with rebuilding the cache. But some files were missing/corrupted. So I booted a rescue CD with kernel 3.7 and ran btrfsck --repair, which repaired quite a few things. After a reboot I