Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [filesystems]

A filesystem is a way to organize and store computer files with their data.

10
votes
0answers
422 views

How to format & mount a large partition with 4k sector size in Freebsd?

gpart show -l: => 6 146239733 da0 GPT (558G) 6 10 - free - (40K) 16 128 1 (null) (512K) 144 262144 2 efi (1.0G) ...
5
votes
0answers
386 views

SSD as Cache for Filesystem (e.g. on HDD or any other)

Can I use SSD (e.g. 512GiB) to be cache for my filesystem (e.g. 16TiB) ? I'd like to avoid my disks on NAS to spin up every day, as when my computers rsync to it, only file sizes, timestamps are ...
5
votes
0answers
1k views

Why are block sizes limited by page size in Linux?

In many (all?) file systems that Linux uses, including ext2/3/4, the maximum block size is the page size of the architecture Linux is running on, ie. 4KiB on x86. Why is there this limit? Might this ...
5
votes
0answers
520 views

Is there a way to show all flags in /proc/mounts?

Some filesystem flags seem to be hidden in /proc/mounts, depending on whether they are defined as defaults. Is there a way to show all flags in /proc/mounts, also including the default ones? And if ...
4
votes
0answers
23 views

How can I find what a process is trying to watch using strace, lsof, and fdinfo?

I have a process (the NewRelic infra agent) that is hung on a RHEL 7, xfs filesystem host. I'm thinking that it's trying to watch a file or maybe a socket that another process already has in use. ...
4
votes
0answers
91 views

Why do ext2 inodes only have 12 direct blocks?

I'm currently writing a hobby file-system for fun. I was wondering if anyone knows why or where I could get information on the design philosophy of ext2. Specifically, I was wondering why each inode ...
4
votes
0answers
265 views

Which filesystem will give me the best performance for both writing and reading small files?

My company developed an application that picks up (watches for) xml files of <10kb in size from a directory, reads it in sends the body as an api call to an external service and then moves the ...
4
votes
0answers
71 views

no such file or directory trying to list or remove file in btrfs

I have a file system mounted btrfs. I have one directory in particular, that I can't remove, because it's listed as non-empty. In that directory, there's one file, which I can see the name of, but ...
4
votes
0answers
203 views

Stress testing storage media — file vs block?

While looking for ways to stress an SDcard, I've noticed there are two ways one can approach this. One is to stress it by reading/writing blocks directly to the device file. For example: sudo ...
4
votes
0answers
807 views

How to interpret fdisk output?

How does one interpret fdisk -l output. I've included a sample output based on an image with my "best guesses", and then show the output based on the device which was used to create the image. ...
4
votes
0answers
2k views

Using dd on Mac OS: conv=fsync equivalent?

I'm running an experiment where I benchmark the speed of reading and writing with and without caching. On Linux, using 'conv=fsync' as an operand makes sure that the output file is entirely physically ...
4
votes
0answers
275 views

Replacing a running binary on read-only file system

I have a simple updater bash script, which replaces files by removing the incident old files and copying new files from an archive to the running embedded target root file system. This way, the script ...
4
votes
0answers
2k views

Disk I/O latency using /proc/vmstat file

How do I calculate disk read and write latency in Linux? Is it possible to do the calculation using /proc file system? I am using iostat and vmstat command. But I do not understand how the ...
4
votes
0answers
2k views

OverlayFS - How to make changes to upper filesystem persistent without unmounting?

I am using an USB drive to start a linux system which needs changes from time to time and also writes some logs. Flash drives tend to fail early if there are many write operations. That brought me to ...
4
votes
0answers
265 views

How does fsnotify setting affect system performance?

Occasionally a software package I install complains that the default fsnotify setting is far too low for decent performance. Intellij IDEA or crashplan are two examples. They suggest using fsnotify ...
4
votes
0answers
2k views

What options are there for tuning Linux file system caching?

What various types of caching are possible in the ext3 file system and how can their values be changed using system calls or other methods? I don't want to use commands or tools.
3
votes
0answers
32 views

Portable, race-free equivalent of mv -T DIR1 DIR2?

It seems mv -T is a GNU extension to mv. Is there a robust way (race-free, portable, and otherwise without "gotchas") to do the equivalent of mv -T dir1 dir2? To be clear: I DO NOT want this to ...
3
votes
0answers
153 views

Failed writes after a while on mounted nfs volume

I have mounted an nfs drive on the machine. I can see it with the following command: $ df -aTh | grep nfs … unrelated volumes … 10.200.30.100:/export/pvc-70..1d nfs4 976M 2.0M 907M 1% /var/lib/...
3
votes
0answers
5k views

ext2fs_open2: Bad magic number in super-block

I'm trying to resize a Linux partition, but after tweaking a lot with this disk I don't know If I have totally corrupted it. Device Boot Start End Sectors Size Id Type /dev/sdd1 * ...
3
votes
0answers
438 views

ext4 mount: mount /dev/mmcblk0p2 on /SD failed: File exists?

If I try mounting the ext4 file system of /dev/mmcblk0p2 into the blank directories I just created: /SD and also /mnt/SD, then the command line answers with: mount: mount /dev/mmcblk0p2 on /SD failed:...
3
votes
0answers
170 views

Is the directory /apps/ a legacy of anything?

Several times, I have seen in (quite) big projects, software installations made under /apps/ First I thought it was a fantasy, refusing FHS normalisation. https://en.wikipedia.org/wiki/...
3
votes
0answers
71 views

Why can the permissions of /sys directories vary across systems?

I have a fresh install of Alpine Linux on my laptop, and I'm trying to read the battery information from /sys/class/power_supply/BAT0/uevent as a regular user (non root). The permissions on the ...
3
votes
0answers
90 views

zfs pool not available on boot after setting noatime and drive idle times with hd-idle / hdparm

At first, I set up my RHEL7-x64 to sleep the zfs drives using this,this, and this. I believe I tried hd-idle first, when the problems began. I had written a script idle_drives_enable to handle ...
3
votes
0answers
197 views

How to mount Atmel mass storage device with unknown FS

I'd like to mount an ATMEL mass storage device (USB) so I can access the data that was recorded to the medical device I was wearing. Below are the commands I've run and the corresponding outputs. ...
3
votes
0answers
5k views

are we going to get a linux module for APFS?

ExFAT doesn't support symbolic links on linux. My git repositories are getting corrupted if I use them on exfat removable media between linux and macOS. Is there any work going on to support APFS on ...
3
votes
0answers
701 views

Disable caching for entire file system or disk?

I have a 1TB M.2 SSD drive that I use for regularly creating really large tarballs. It just has an ext4 file system on it at the moment. Is there some way I can tell the kernel not to cache data on ...
3
votes
0answers
121 views

How to hidepid on Arch Linux manually?

I have reinstalled Arch Linux to find that the package which used to be available called hidepid no longer exists, so I have to do this manually, but as I am still relatively new to Arch, I am not ...
3
votes
0answers
175 views

How to repair btrfs after broken sata cable?

A few days ago my btrfs raid56 filesystem was suddenly mounted read-only. Smartctl -all returned nothing but an error for one of the disks and after replacing the sata-cable the disk now shows its ...
3
votes
0answers
86 views

How to approach planning a BSD file server's outward-facing file hierarchy

I'm migrating data on an informal home server to a new FreeNAS (FreeBSD 10) based file server running samba, and I'm stuck in trying to plan how to lay the data out, to give correct access to ...
3
votes
0answers
209 views

Problem copying a directory larger than 6 GB

I have a problem when I want copy a directory to a disk external, but the directory has size 6 GB. When try copy it, it gives me a error: " File too large", I give more information, that directory ...
3
votes
0answers
46 views

Finding files contained in particular block group

How do I see/list what files have blocks in a particular block group? I'm looking at a small disk image with an ext3 file system. Can I use debugfs, and if so, how?
3
votes
0answers
47 views

software-level error detection and correction for raw storage

If I understand data storage correctly, all storage devices are unreliable to some extent, which is why most have hardware-level abstraction layers. Hard drives use error correction. If a sector is ...
3
votes
0answers
1k views

Difference in space reserved for inodes in ext4 and XFS partitions

I am formatting a couple of 60G Logical Volumes (vg01-logs and vg01-monitoring) in one of our servers. These partitions will hold a large number of small files, so I want them with more than the ...
3
votes
0answers
2k views

How to mount ufs file system under Debian testing?

In order to mount my /dev/sda4 under /mnt/ufs_mount on Debian Testing , i have tried the following commands (it works fine under Debian Jessie): modprobe ufs mount -r -t ufs -o ufstype=ufs2 /dev/...
3
votes
0answers
783 views

FUSE Overlay filesystem for “too long filenames”

Is there FUSE overlay filesystem, that: * resolve on it's own "too long filenames" for underlying filesystem * otherwise (for filenames fitting into limits of underlying filesystem) just proxy 1:1 ? ...
3
votes
0answers
2k views

Wrong inode: corrupted f2fs, fsck.f2fs cannot repair

A f2fs partition on my Android phone has recently become corrupted. It will still mount fine; however, I completely lost access to one directory (/data/media/0), which now shows as empty. Yet the disk ...
3
votes
0answers
1k views

EXT4 Journaling - Problem

Basically my root (/) ext4 partition keeps being mounted as read-only when I apply internal journaling feature. I understand that this should be default, but today I had been trying to apply external ...
3
votes
0answers
846 views

Mount LVM volume as external usb drive? CentOS 6

I'm trying to mount my old 2x500GB drives to the new server which has the same drive volume. Both have LVM structure but it's not working. root@server [/mnt/usb]# ls /dev/sd* /dev/sda /dev/sda2 /...
3
votes
0answers
91 views

Mapping a physical sector to a filename

I just finished using ddrescue to recover the contents of a failing hard drive. It was able to recover everything but two sectors. How do I figure out which files (if any) occupied those sectors? ...
3
votes
0answers
182 views

Problems with file system

I created a partition with EXT4 file system and when I'm writing in this partition frequently the Kernel return the following error: Jan 01 01:17:54 infobuffer360 kernel: r7:c0561280 Jan 01 01:17:54 ...
3
votes
0answers
284 views

shared filesystem with offline access

I would like a shared filesystem with offline access. I have two machines. One is a light laptop with a small amount of SSD storage that I carry with me. The other is a stay-at-home computer with much ...
3
votes
0answers
1k views

No space left on device, with 320 GB free

I'm a bit lost. I have a 500 GB external hard drive with its original filesystem still in place. The last command (dd writing to a file within this filesystem) failed with "no space left on device". ...
3
votes
0answers
232 views

On which disk is a file located in a btrfs RAID-1 array/filesystem?

I have a btrfs array with 5 disks in RAID-1 mounted on /mnt/array: # btrfs filesystem show /mnt/array Label: 'nicefilesystem' uuid: censored Total devices 5 FS bytes used 4.95TiB ...
2
votes
0answers
35 views

Automatic symlink to latest folder

Is there a way in Linux to automatically maintain a symlink to the latest version of a file/folder in a certain location? My use case: I generate datasets with unique job names, then write them to a ...
2
votes
0answers
21 views

Are released blocks logged in the journal for ext4?

Suppose we have a simple case: ext4 file system with journaling a single file named file, which has no other hard links the inode for file has associated with it only 1 data block My understanding ...
2
votes
0answers
45 views

How to trim down Amazon Linux OS for more free space?

I use EC2 on Amazon Web Services. The OS of the t2.micro instance is a customized “Amazon Linux” with 1 GiB RAM and 1 vCPU. When accessing this instance via their Cloud9 IDE I find that by default ...
2
votes
0answers
97 views

processes hanging when trying to access a file

I'm running Ubuntu 16.04.5 and the ext4 filesystem, and I have a file which causes processes to hang when they read it. For example: $ cat /path/to/file.txt and then from a separate terminal: $ ...
2
votes
0answers
17 views

Find the size of all relevant caches when doing I/O

So, I'm looking at the stats from iostat, which updates every few seconds, and I see that I/O to device happens in bulks, say, around 40M/s, once every half a minute or so. I'm debugging an ...
2
votes
0answers
302 views

Cannot delete a btrfs subvolume

I have an Arch Linux Installation on a btrfs filesystem partition "/dev/sda1": [root@larch ~]# mount | grep sda /dev/sda1 on / type btrfs (rw,relatime,ssd,space_cache,subvolid=266,subvol=/subvol_root)...
2
votes
0answers
37 views

meaning of @ in (btrfs?) pathnames

I have noticed that Synology NAS devices preface many system-relevant links or directory names with the @ character. I've just noticed that the standard partitioning in openSUSE does the same when ...