similar to: Possible to dedpulicate read-only snapshots for space-efficient backups

Hello, some questions regarding btrfs deduplication. - What is the state of it? Is it "safe" to use? https://btrfs.wiki.kernel.org/index.php/Deduplication does not yield much information. - https://pypi.python.org/pypi/bedup says: "bedup looks for new and changed files, making sure that multiple copies of identical files share space on disk. It integrates deeply with btrfs so

Welcome, I''ve been using btrfs for over a 3 months to store my personal data on my NAS server. Almost all interactions with files on the server are done using unison synchronizer. After another use of bedup (https://github.com/g2p/bedup) on my btrfs volume I experienced huge perfomance loss with synchronization. It now takes over 3 hours what have taken only 15 minutes! File

Hi. I am seriously considering employing btrfs on my systems, particularly due to some space-saving features that it has (namely, deduplication and compression). In fact, I was (a few moments ago) trying to back up some of my systems to a 2TB HD that has an ext4 filesystem and, in the middle of the last one, I got the error message that the backup HD was full. Given that what I backup there are

Originally from https://github.com/markfasheh/duperemove/blob/master/btrfs-extent-same.c Signed-off-by: Gabriel de Perthuis <g2p.code+btrfs@gmail.com> --- .gitignore | 1 + Makefile | 2 +- btrfs-extent-same.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 147 insertions(+), 1 deletion(-) create mode 100644 btrfs-extent-same.c diff

Hi, The following series of patches implements in btrfs an ioctl to do out-of-band deduplication of file extents. To be clear, this means that the file system is mounted and running, but the dedupe is not done during file writes, but after the fact when some userspace software initiates a dedupe. The primary patch is loosely based off of one sent by Josef Bacik back in January, 2011.

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

Hello, I have a filesystem that has become unusable because of a balance I can''t stop. It is very close to full, and the balance is preventing me from growing it. It was started like this: sudo btrfs filesystem balance start -v -musage=60 -dusage=60 /srv/backups It has been stuck at 0% across reboots and kernel upgrades (currently on 3.8.1), and cancelling it had no effect: Balance

On Sat, 01 Jun 2013 20:54:15 +0100, Richard W.M. Jones wrote: > On Sat, Jun 01, 2013 at 02:27:50PM +0000, Gabriel de Perthuis wrote: >> Hello, >> As I understand it guestfs appliances normally work as servers >> and run high-level commands from some external channel. > > This is the normal architecture when you're using libguestfs to access > a VM or disk image:

Dear All, I have a very slow deduplication going on on an external usb disk. I'm using it for backups - I rsync the relevent files to the disk and then take a snapshot. I then deduplicate with bedup dedup <disk-mount-point> What I am finding is that it is reporting a deduplication between the data on the disk and its snapshot e.g.: Deduplicated: -

According to https://github.com/g2p/bedup/tree/wip/dedup-syscall "The clone call is considered a write operation and won''t work on read-only snapshots." Is this fixed on newer kernels? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at

Hello, I was bored this weekend so I hacked up online dedup for Btrfs. It''s working quite well so I think it can be more widely tested. There are two ways to use it 1) Compatible mode - this is a bit slower but will handle being used by older kernels. We use the csum tree to find duplicate blocks. Since it is relatively easy to have crc32c collisions this also involves reading the

Just a quick update, I''ve dropped the hashing stuff in favor of doing a memcmp in the kernel to make sure the data is still the same. The thing that takes a while is reading the data up from disk, so doing a memcmp of the entire buffer isn''t that big of a deal, not to mention there''s a possiblity for malicious users if there is a problem with the hashing algorithms we

Hello If I want to manage a complete disk with btrfs, what''s the "Best Practice"? Would it be best to create the btrfs filesystem on "/dev/sdb", or would it be better to create just one partition from start to end and then do "mkfs.btrfs /dev/sdb1"? Would the same recomendation hold true, if we''re talking about huge disks, like 4TB or so?

Glück Auf! I know its been discussed more then ones, but as a user I really would like to see the patch for allowing this in the kernel. Some users tested this patch successfully for weeks or months in 2 or 3 kernel versions since then, true? I''d say by creating a snapshot, it''s nothing else in the end. More then one file or tree sharing the same data on disc, or am I wrong?

Hi, I''ve observed a rather strange behaviour while trying to mount two identical copies of the same image to different mount points. Each modification to one image is also performed in the second one. Example: dd if=/dev/sda? of=image1 bs=1M cp image1 image2 mount -o loop image1 m1 mount -o loop image2 m2 touch m2/hello ls -la m1 //will now also include a file calles "hello"

Hello, As I understand it guestfs appliances normally work as servers and run high-level commands from some external channel. But it might be possible to bundle a guestfish script to run commands from and do away with the external system. That would make it useful on non-virtualised systems. Has anyone tried this already?

Hello, I''ve stumbled upon this article: http://storagemojo.com/2011/06/27/de-dup-too-much-of-good-thing/ Reportedly Sandforce SF1200 SSD controller does internally block-level data de-duplication. This effectively removes the additional protection given by writing multiple metadata copies. This technique may be used, or can be used in the future by manufactureres of other drives too. I

In reading this blog post: http://blogs.sun.com/bobn/entry/taking_zfs_deduplication_for_a a question came to mind..... To understand the context of the question, consider the opening paragraph from the above post; Here is my test case: I have 2 directories of photos, totaling about 90MB > each. And here''s the trick - they are almost complete duplicates of each > other. I downloaded

Hello btrfs! Recently I upgraded to 3.2.0-rc4 due to instabilities with my btrfs filesystem in 3.1.1. While with 3.1.1 my system completely froze, with 3.2.0-rc4 it stays at least somehow usable (for some strange reason my xorg screen turns black as soon as this happens, only ssh is working then). Scrubbing reports 1 uncorrectable error. I have this error since my system froze due to some

In the future, it would be cool if there were a mailbox format (dbox2?) where mail headers and each mime part were stored in separate files. This would enable the zfs dedup feature to be used to maximum benefit. In the zfs filesystem, there is a dedup feature which stores only 1 copy of duplicate blocks. In a normal mail file, the headers will be different for each recipient and the chances of