similar to: Lots of trouble hanging when rm files with many extents

I''m trying to use this feature of qgroup: btrfs qgroup assign <srcid> <destid> <path> Assigns the lower level qgroup src to the higher level qgroup dest in the btrfs found in <path>. It is used to build qgroup hierarchies. However, I fail to understand how this feature should work, and I''m getting "ERROR: bad relation requested":

Not sure if it''s anything interesting - I had the following entry in dmesg a few days ago, on a server with 32 GB RAM. The system is still working fine. [1878432.675210] btrfs-qgroup-re: page allocation failure: order:5, mode:0x104050 [1878432.675319] CPU: 5 PID: 22251 Comm: btrfs-qgroup-re Not tainted 3.11.0-rc7 #2 [1878432.675417] Hardware name: System manufacturer System Product

I converted an ext4 filesystem with btrfs-convert, mounted it, and wanted to do "lzop -d ...". The result was an immediate Oops (btrfs is on LVM, on dm-crypt, on /dev/sdb which is USB-connected). mini-904.img.lzo dentry_open failed BUG: unable to handle kernel paging request at ffffffcd IP: [<c01b5f36>] fput+0x6/0x30 *pde = 00575067 *pte = 00000000 Oops: 0002 [#1] SMP last sysfs

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

At the beginning of August, Mikulas Patocka posted to linux-kernel mailing list about adding snapshot merging to LVM[1]. Basicaly, snapshot merging means that it is possible to turn a snapshot back into its origin. Using LVM, however, means that you need to have free place outside of the filesystem (i.e., in physical volume) to make snapshots, which is not always possible on workstations and

I''ve enabled "extended inode refs" and "skinny metadata extent refs" with btrfstune. Then, I''ve tried running "btrfs filesystem balance" - unfortunately it segfaulted. (not sure if I should run balance operation after using btrfstune with -r and -x)? This is with 3.10 kernel with "Btrfs: make backref walking code handle skinny metadata"

Hi list, I don''t trust theoretical benchmarks that much and prefer "real-life benchs" on the occasion, so here''s mine: Given 4 laptops, the most powerful of which was running BTRFS and the others ext3 or ext4, all machines running Ubuntu 11.04 Natty 32-bit with a stock Ubuntu 2.6.38-11 kernel, all machines were given the following FS-intensive task : - Upgrade

Christoph Hellwig wrote: > There are a lot of variables when using qemu. > > The most important one are: > > - the cache mode on the device. The default is cache=writethrough, > which is not quite optimal. You generally do want to use cache=none > which uses O_DIRECT in qemu. > - if the backing image is sparse or not. > - if you use barrier - both in the host

When data in a file is overwritten, starting somewhere in the middle of the file, the overwritten space is counted twice against the space usage numbers. Is this a bug, or did I something wrong? This is what I did: I create a subvolume and limit it to 4 MB, and create a 1000 KB file in the subvol: # btrfs subvol create s Create subvolume ''./s'' # btrfs

This is a first draft of a subvolume quota implementation. It is possible to limit subvolumes and any group of subvolumes and also to track the amount of space that will get freed when deleting snapshots. The current version is functionally incomplete, with the main missing feature being the initial scan and rescan of an existing filesystem. I put some effort into writing an introduction into

Hi gang, I was a little surprised to see that patch go by recently which fixed an endian bug. I went to see how sparse checking looked and it was.. broken. I got it going again in my Fedora environment. Most of the patches are just cleanups, but there *were* three real bugs lurking in all that sparse warning spam. So I maintain that it''s worth our time to keep it going and fix

I''ve been thinking about this for a while, from a perspective of how to make it work by allocating i-node numbers from a global pool, but yesterday I realized that offering the feature would be a bad idea because it violates the semantics of file systems. I will be happy to expand on that point if anyone disagrees with it. dln -- "It is merely a matter of persistence." --

I notice this question on the wiki/faq: https://btrfs.wiki.kernel.org/index.php/UseCases#What_is_best_practice_when_partitioning_a_device_that_holds_one_or_more_btr-filesystems and as it hasn''t been answered, can anyone make any comments on the subject Various things come to mind: a) partition the disk, create an LVM partition, and create lots of small LVs, format each as btrfs b)

For using SSDs: Are there any format/mount parameters that should be set for using btrfs on SSDs (other than the "ssd" mount option)? General questions: How long is the ''delay'' for the delayed alloc? Are file allocations aligned to 4kiB boundaries, or larger? What byte value is used to pad unused space? (Aside: For some, the erased state reads all 0x00, and for

Hello, We are using btrfs filesystems in our infrastructure and, at some point of time, they start refusing to create new subvolumes. Each file system is being quota initialized immediately after its creation (with "btrfs quota enable") and then all subfolders under the root directory are created as subvolumes (btrfs subvolume create). Over time, these subvolumes may also be

Hello, I''m currently trying to understand how compression in btrfs works. I could not find any detailed description about it. So here are my questions. 1. How is decided what to compress and what not? After a fast test with a 2g image file, I''ve looked into the extents of that file with find-new and it turned out that only some of the first extents were compressed. The file was

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> ---

Here are patches to do offline deduplication for Btrfs. It works well for the cases it''s expected to, I''m looking for feedback on the ioctl interface and such, I''m well aware there are missing features for the userspace app (like being able to set a different blocksize). If this interface is acceptable I will flesh out the userspace app a little more, but I believe the

I noticed a huge problem with the free space cache that was presenting as an early ENOSPC. Turns out when writing the free space cache out I forgot to take into account pinned extents and more importantly clusters. This would result in us leaking free space everytime we unmounted the filesystem and remounted it. I fix this by making sure to check and see if the current block group has a cluster

When replaying a log tree with qgroups enabled, tree_mod_log_rewind does a sanity-check of the number of items against the maximum possible number. It calculates that number with the nodesize of fs_root. Unfortunately fs_root is not yet set at this stage. So instead use the nodesize from tree_root, which is already initialized. Signed-off-by: Arne Jansen <sensille@gmx.net> ---