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.

1986 questions
11
votes
1 answer

How can I recover an ext4 filesystem corrupted after a fsck?

I have an ext4 filesystem on luks over software raid5. The filesystem was operating "just fine" for several years when I was beginning to run out of space. I had a 9T volume on 6x2T drives. I began upgrading to 3T drives by doing the mdadm fail,…
Regan
  • 1,011
  • 1
  • 7
  • 15
11
votes
9 answers

What's the best file-system for storing virtual machine images?

I'm planning how to partition my hard drive. I want to have 2 partitions - one for Ubuntu, the main operating system, and the other for virtual machine images, as I want to run virtual machines of Windows and MacOS through VirtualBox. My question is…
11
votes
2 answers

Making SD card corruption-proof

My embedded linux device uses an SD card for saving certain diagnostics data, far too copious for internal flash. The problem is if the device is switched off unexpectedly, the filesystem (FAT32) on the card is corrupted. There is no way to prevent…
SF.
  • 277
  • 3
  • 9
11
votes
1 answer

Linux ext4 "extents" attribute

I noticed the e attribute on several files/directories on Linux machines installed on ext4 filesystems. [kelly@p2820887.pubip.serverbeach.com ~]$ lsattr -d /bin -------------e- /bin According to chattr(1): The ’e’ attribute indicates that the file…
tylerl
  • 15,055
  • 7
  • 51
  • 72
11
votes
5 answers

How to allow users to transfer files to other users on linux

We have an environment of a few thousand users running applications on about 40 clusters ranging in size from 20 compute nodes to 98,000 compute nodes. Users on these systems generate massive files (sometimes > 1PB) controlled by traditional unix…
Jon Bringhurst
  • 251
  • 2
  • 8
11
votes
10 answers

How does the number of subdirectories impact drive read / write performance on Linux?

I've got an EXT3 formatted drive on a Linux CentOS server. This is a web app data drive and contains a directory for every user account ( there are 25,000 users ). Each folder contains files that that user has uploaded. Overall, this drive has…
T. Brian Jones
  • 927
  • 4
  • 17
  • 29
11
votes
5 answers

What is the partition id / filesystem type for UDF?

This is probably trivial to check using cfdisk on a UDF-formatted CD/DVD/Blu-Ray, but I have neither of them at hand. I have created an UDF formatted partition on a USB hard drive to share data between Linux and Windows computers (FAT doesn't handle…
skolima
  • 1,263
  • 3
  • 16
  • 28
11
votes
3 answers

How can I add the "noatime" flag to my / filesystem without a reboot

Would the remount command do it if I add the option in /etc/fstab? Is this this a good idea?
ckliborn
  • 2,778
  • 4
  • 25
  • 37
11
votes
4 answers

How can I find out where a file is physically located on the disk (block numbers)?

This is an obscure question, I know. I'm trying to do some performance testing of some disks on a Linux box. I'm getting some inconsistent results, running the same test on the same disk. I know that disks have different performance depending on…
Rick Koshi
  • 917
  • 3
  • 14
  • 22
11
votes
3 answers

disk space overhead in ext4

I'd like to know if there's some rule (or formula) I can apply to find out how much of disk space will be used by the filesystem in an ext4 partition. for example, in a partition of 100 GB, how much can I actually use? does it depend on other…
cd1
  • 1,484
  • 4
  • 12
  • 17
11
votes
6 answers

Tips on efficiently storing 25TB+ worth million files in filesystem

Say you are confronted with 25 TB worth uncompressed log files and you have at your disposal an array of 20 commodity boxes with collective free storage capacity of 25 TB. How would you store these ?. a) Which distributed file system to use ? b)…
Ankur Gupta
  • 230
  • 2
  • 8
11
votes
4 answers

What is a Journaling file system?

What is a Journaling file system? Even wikipedia doesn't give much information. Apart from NTFS which other file systems(on Windows / Linux) support journaling and how does it give a performance boost?
Prasoon Saurav
  • 347
  • 3
  • 8
11
votes
6 answers

How do I get transparent, efficient, file system snapshotting or versioning on ext3/4?

I've long thought about versioning file systems. This is a killer feature and I've looked at Wayback, ext3cow, zfs, fuse solutions, or just cvs/svn/git overlays. I consider ext3cow the model for my requirements. Transparent, efficient, but I can do…
Dale Forester
  • 241
  • 2
  • 5
11
votes
1 answer

Best practices for choosing fs block size on ext3/4?

I never really pay block size much attention but obviously there can be benefits to choosing something other than the default. I am looking for a good "best practices" paper on choosing block size. Also, when used on top of LVM is it's performance…
CarpeNoctem
  • 2,437
  • 4
  • 23
  • 32
10
votes
1 answer

How do I expand the root's volume size?

I have Ubuntu Server 18.04 LTS running off a 16GB SanDisk USB pendrive in my server. From what I can remember, when I installed Ubuntu on there I had enabled LVM support. For some reason, when I ssh into my server, it says / is using 99.6% of…
leetbacoon
  • 203
  • 1
  • 2
  • 7