Questions tagged [filesystems]

A file system (or filesystem) is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device(s) which contain it.

A file system (or filesystem) is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device(s) which contain it. A file system organizes data in an efficient manner and is tuned to the specific characteristics of the device. A tight coupling usually exists between the operating system and the file system. Some file systems provide mechanisms to control access to the data and metadata. Ensuring reliability is a major responsibility of a file system. Some file systems allow multiple programs to update the same file at nearly the same time.

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GlusterFS vs Ceph, which is better for production use for the moment?

I am evaluating GlusterFS and Ceph, seems Gluster is FUSE based which means it may be not as fast as Ceph. But looks like Gluster got a very friendly control panel and is ease to use. Ceph was merged into linux kernel a few days ago and this…
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To fsck or not fsck after 180 days

By default after 180 days or some number of mounts, most Linux filesystems force a file system check (fsck). Of course this can be turned off using, for example, tune2fs -c 0 -i 0 on ext2 or ext3. On small filesystems, this check is merely an…
Michael Havas
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ext4 listing of files very slow in one specific directory that contained lots of files before

Background I had a small logrotate misshap... Logrotate would rotate the archived logs by misstake causing a quadratic growth of files in my /var/log/. And by the time I caught wind that something was awry, /var/log/ already contained a few million…
Emma
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zfs rename/move root filesystem into child

Similar question exists but the solution (using mv) is awful because in this case it works as "copy, then remove" rather than pure "move". So, I created a pool: zpool create tank /dev/loop0 and rsynced my data from another storage in there directly…
Anton
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Read/write access for passthrough (9p) filesystems with libvirt/qemu?

I have recently started experimenting with the support for passthrough filesystems in recent versions of KVM/QEMU/libvirt. Making the filesystems available for read access has "just worked", but I'm a little puzzled about how write access is…
larsks
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How to list content from a tar file without recursion?

I've a tar (gz, bzip) file and want to see its content, but not recursively. This is: The "first level" in the file. I already know how to see content: tar -ztf file.tar.gz But it's recursive!! Thanks!
santiago.basulto
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Too many open files on Debian

I have long running process at Debian. At some point in throw an error: Too many open files. Running: ulimit -a shows: open files (-n) 1024 I wish to increase number of open files in 2 times. After execution ulimit -n…
FoxyBOA
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How to compare two directories (including sub directories) for differences?

How can I compare two directories with sub dirs to see where is the difference?
alexus
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Program file exists in /usr/bin, but cannot be used

Clearly my file exists in /usr/bin $ ls /usr/bin/ngrok /usr/bin/ngrok However, when I attempt to chown it I receive an error $ sudo chown my_user:users /usr/bin/ngrok chown: cannot dereference '/usr/bin/ngrok': No such file or directory Further…
Jorik
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In *nix, how to determine which filesystem a particular file is on?

In a generic, modern unix environment (say, GNU/Linux, GNU/Solaris, or Mac OS X), is there a good way to determine which mountpoint and filesystem-type a particular absolute file path is on? I suppose I could execute the mount command and manually…
smokris
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Is there a hard limit to the number of files a directory can have?

Wondering if there is a limit to the number of files that can be stored inside a directory, in CentOS 6. There is one particular directory which could potentially have millions of subdirectories. Storage capacity aside, is there a limit to the…
Juan Carlos Coto
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Vagrant shared folder and file change events

I have ubuntu virtual machine that I'm accessing through Vagrant. On my host (Mac OSX), there is a folder with couple of files, that I share to virtual machine. In that virtual machine, I want to use guard to watch for files changes and perform some…
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Calculating total file size by extension in shell

We have a set of directories containing lucene indexes. Each index is a mix of different file types (differentiated by extension) eg: 0/index/_2z6.frq 0/index/_2z6.fnm .. 1/index/_1sq.frq 1/index/_1sq.fnm .. (it's about 10 different…
barnybug
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max files per directory in ext4

I manage an application that contains a filestore in which all the files are stored with the filenames equal to their md5 sums. All files are stored in one directory. Currently there are thousands, but soon their should be millions of files on the…
Jeroen Ooms
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Production-ready, highly reliable filesystems on Linux: ext4 ext3 XFS or JFS (or ZFS)?

The last real question I've seen on this topic is from about two years ago (is ext4 ready for production usage). In the intervening time, how has ext4 improved? XFS, JFS, and ext3 are the standby reliable choices. I've only used ext4 on recent…
warren
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