search for: filefrag

While exploring some btrfs maintenance with respect to defragmenting I ran the following commands: # filefrag /path/to/34G.file /path/to/5.7G.file /path/to/34G.file: 2406 extents found /path/to/5.7G.file: 572 extents found Thinking those mostly static files could be less fragmented I ran: # btrfs filesystem defragment -c /path/to/34G.file # btrfs filesystem defragment -c /path/to/5.7G.file and to my surp...

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 appreciated ;-) TIA. -- Swâmi...

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 or...

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, 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 9 extents With such a file a sequential read is quite slow (~76MB vs >200MB on my raid c...

Is there a way to find the holes in sparse files, other than assuming contiguous blocks of zeroes are holes? Thanks, Sean

...cular 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 would happen. So doing that would be an acceptable solution to my issue below, but I''m curious as to what''s happening. Filefrag reports that a VM image file has 4744 extents. If I run btrfs fi defrag -v /path/to/file.vmdk, it returns immediately with no messages but an exit status of 20, and running filefrag again shows that no defragmentation has taken place. This is on Ubuntu 13.04, kernel 3.9.0-rc8 and v0.20-rc1 of t...

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

...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 ''filefrag'' as well as ''filefrag -v''. Both reported the same number. I don''t know if this has anything to do with having snapshots at all because files that haven''t been snapshotted yet are affected by this. Disk space isn''t an issue since my 1TB disk isn&...

...uoso.log -rw-r--r-- 1 martin martin 0 Jan 27 17:52 soprano-virtuoso.pxa -rw-r--r-- 1 martin martin 8,0M Jan 31 14:07 soprano-virtuoso-temp.db -rw-r--r-- 1 martin martin 14K Jan 31 14:07 soprano-virtuoso.trx martin@merkaba:~/.kde/share/apps/nepomuk/repository/main/data/virtuosobackend> sudo filefrag soprano-virtuoso.db [sudo] password for martin: soprano-virtuoso.db: 481 extents found […] martin@merkaba:~/.kde/share/apps/nepomuk/repository/main/data/virtuosobackend> sudo btrfs filesystem defragment soprano-virtuoso.db martin@merkaba:~/.kde/share/apps/nepomuk/repository/main/data/virtuoso...

...6done ) = 6 exit_group(0) = ? +++ exited with 0 +++ root@debian:~# I did manage to find two calls to fsync in the e2fsprogs source which are not return-value-checked: https://github.com/tytso/e2fsprogs/blob/956b0f18a5ddb6815a9dff4f10a1e3125cdca9ba/misc/filefrag.c#L303 https://github.com/tytso/e2fsprogs/blob/956b0f18a5ddb6815a9dff4f10a1e3125cdca9ba/lib/ext2fs/unix_io.c#L915 I'll see about submitting a patch there. I'm not sure where to start with hunting down why mkfs's pwrite() calls aren't failing. I'd look to the kernel source for...

What happens if you set an individual file inside a subvolume as nocow (chattr +C) and then take a snapshot of that subvolume and modify the file in both? Will btrfs now ignore the nocow attribute completely or will it do "as few copies as possible"? (I''d love to know if it''s possible to visualize the fragmentation of a single file.) -- To unsubscribe from this list:

Hi, I need to understand and to calculate the offset of the beginning of a file within my partition which uses an ext3 filesystem. Can I use dumpe2fs to figure that out, if yes how? Sincerely, William Tambe

Let me preface this by saying "Yes, I know *nix filesystems don't need to worry about fragmentation". That said, is there a way to check the overall level of fragmentation of a live ext3 filesystem? I know about filefrag, but that's for specific files. And I think e2fsck tells you, but only if you take the filesystem offline for the scan. Is there anything that will give a percentage for a *live* filesystem? (I have a fs that's been at >95% usage for quite some time, and I want to check for any fr...

https://bugzilla.samba.org/show_bug.cgi?id=11588 Bug ID: 11588 Summary: missing option: preallocate for all files except for sparse Product: rsync Version: 3.1.2 Hardware: x64 OS: Linux Status: NEW Severity: enhancement Priority: P5 Component: core

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

I find these Linux user comments about not suffering from fragmentation curious. I just tested decoding a flac in Fedora 20 and filefrag command reports the decoded file is in 8 extents. Different name but same thing. On 26.9.2014 14:08, Erik de Castro Lopo wrote: > Martijn van Beurden wrote: > >> Can you please wrap the setvbuf in _WIN32 IFDEFs too? Currently >> memory usage of FLAC decoding is about 1MB, so thi...

Hi! I'm going to build a maildir-based mailserver with a ~56 gb mail-partition. What blocksize/bytes-per-inode/number of inodes should i use (i don't want to ran out of inodes and don't want to sacrifice too much space for filefragments)? Is there a drawback when lowering the blocksize/increasing the number of inodes (except the maximum filesystem size)? The inodes used by a file is always filesize divided by the blocksize rounded up to the next absolute value, isn't it? best regards, Michael Renner

Hi, you know command filefrag can get the block numbers of a file, but how to get the sector numbers of a file ? thanks ! -- Regards, Sucan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://listman.redhat.com/archives/ext3-users/attachments/20090607/5eb3a0e2/attachment.htm>

I was Googling around for ways to check fragmentation on Btrfs, and I came across the ''filefrag'' command. Even though it is a ext2/3 command, it seems to work on Btrfs files since it uses the FIEMAP ioctl to determine the number of extents. From a bash prompt, I found I could examine large sections with something like: # for file in $(find <PATH/TO/BTRFS/VOL/> -type f); do f...