Questions tagged [tmpfs]

tmpfs is a common name for a temporary file storage facility on many Unix-like operating systems. It is intended to appear as a mounted file system, but stored in volatile memory instead of a persistent storage device.

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How to read tmpfs as a block device in linux?

A typical linux machine mounts a tmpfs to store temporary files: $ df Filesystem Size Used Avail Use% Mounted on /dev/sda1 953M 702M 203M 78% / tmpfs 1.5G ...
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Cannot use newfs_hfs on ramdisk

I tried ramfs_size_mb=2048 mount_point=/usr/local/var/mysql # 1024 bytes per kibibyte # 1024 kibibytes per mebibyte # 512 bytes per sector ramfs_size_sectors=$((${ramfs_size_mb}*1024*...
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Why am I able to mount arbitrary TMPFS as an unprivileged user with unshare?

While messing around with unshare, I stumbled on the following behavior in an unprivileged shell: foo@pc $ id foo uid=1000(foo) gid=1000(foo) groups=1000(foo),27(video),97(input) foo@pc $ unshare -r -...
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How to take full advantage of your RAM on Linux

On the downloads page of Garuda Linux, they say that "we believe in the principle that unused RAM is wasted RAM". There are some performance comparisons on youtube, it wasn't well in stress ...
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Syncing Docker tmpfs to Disk?

I have a couple of Docker containers that constantly write to logs. This causes continuous disk I/O, particularly writes. Is there a way to make Docker read/write to a ramdisk, which could ...
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How to create ramdisc for Prestashop cache on Debian

Recently I was struggling to create ram disk for Prestashop cache folder which will have read and write privilages. I am using Apache + Nginx (as reverse proxy) and PHP-FPM 5.6 (soon moving to 7.2) ...
1 vote
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Docker system directories in tmpfs?

Does it make sense to mount any of Docker directories under /var/lib/docker as tmpfs to speed things up and reduce SSD wear? ~ # l /var/lib/docker/ total 56 drwx------ 2 root root 4096 Jul 28 02:02 ...
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How can I run postgres with data dir on /tmp?

I'm running automated integration tests using data stored in a postgres database. I need to start every test run with the same database contents. Instead of always clearing the database and importing ...
1 vote
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Give space to a tiny computer (tmpfs with swap over nfs)

I have a tiny computer with not so much RAM (1-2GiB) and very little disk space in which I installed Gentoo. I also have space on a shared NFS. In order to be able to compile any package, even the ...
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Should I expect programs that run from a tmpfs folder to run faster? (with and without I/O, inside and outside a Docker container)

On Linux, suppose I have an executable file. Let's look at two cases: (A) A large portion of what the executable does is disk I/O; (B) the executable doesn't do any disk I/O. For each of the cases A ...
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Prevent filesystem caching on tmpfs

Suppose that I want to put a big file (or a bunch of files) into a TMPFS, for whatever reason. Using dd with various combinations of direct and nocache flags, whether I copy a file from disk or create ...
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Why my /tmp on Debian 9 have 15GB

My Debian 9 /tmp folder have 15GB (44 days uptime). Am I supposted to manually (or with cronjob) delete /tmp contents? OR something is wrong :D
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When mounting dir to RAM, will contents remain after computer reboot

I mounted a cache directory to tmpfs for faster performance on my website using this command: tmpfs on /var/cache type tmpfs (rw,relatime,size=102400k,mode=777) It seems to be working well, however, ...
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systemd: disable useless tmpfs

Context: embedded system, read-only MMC with tmpfs overlay. Everything gets written to RAM & disappears on reboot. systemd insists on creating numerous tmpfs mounts (at least /run /run/lock /run/...
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Changing permissions of /tmp

I know that 1777 is the default mode of /tmp on many Linux distros. I haven't been able to find much online, but I'm wondering if making /tmp group- and/or world-readable is really necessary. Can ...
2 votes
1 answer
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Linux tmpfs write speed slower than RAM speed

I have a HPE ProLiant DL360 Gen9 server, specs are: CPU: Intel Xeon 2 CPUs E5-2687W v3 @ 3.10GHz, 25MB L3 cache, 10 cores ea RAM: 8x 32GB PC4-17000 DDR4 2133MHz CAS-15 1.2V SDRAM DIMM (256 GB total) ...
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Differences between symlink to /tmp and tmpfs

I'm trying to make a read-only file-system (Raspbian). One common way is to place some directory (that are to be writable) in a tmpfs. Example, I found some tutorials that suggest: rm -rf /var/lib/...
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How can I efficiently force VirtualBox to use /dev/shm for all VM files?

SuperUsers. I want to preserve the life of my laptop's SSD drive. I make heavy use of Vagrant, Chef, and Virtualbox. I'm using Test Kitchen w/ Vagrant to run my infrastructure code tests. I am ...
1 vote
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Is it possible to create tmpfs inside lvm puppet module?

we have autoprovisioning of linux machines (using trusty and xenial) and we are using puppet for it. We are using LVM in puppetlabs/lvm and specifying it in hiera. Example: lvm::volume_groups: ...
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1 answer
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OverlayFs merge on unmount

For performance reasons I would like to stack tmpfs on top of the working directory of some programs. However, the program needs to access data previously saved in the "real" working directory, ...
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tmpfs — deleting files won't free the space

Using fedora@latest, I have /tmp mounted as a tmpfs. Sometimes I run some program that stores large files into it, until I fill it entirely. I try to delete some files manually, hoping to free space,...
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How to use tmpfs and SSD for smart cache

I want to create fast logical disk under Linux for storing temporary files. This files I don't afraid to lost. On my machine I have 128Gb of RAM and 512Gb of SSD disk. So I want use 50% of my RAM as ...
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DD-WRT: /tmp folder permissions

After making a simple hello world OpenWRT package I installed it to the /tmp folder on the dd-wrt device. The program shows up in ls /tmp but when I try to execute it, it shows me /tmp/helloworld: ...
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Where's my RAM disk being stored?

I'm running an Ubuntu VM under Windows 7, within the VM I've allocated a 5GB RAM disk using sudo mount -t tmpfs -o size=5G tmpfs /mnt/gitRAM and then copied files into it. When I then look at conky ...
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Why is a second "tmpfs" parameter necessary when mounting a tmpfs?

Excerpted from the documentation So 'mount -t tmpfs -o size=10G,nr_inodes=10k,mode=700 tmpfs /mytmpfs' will give you tmpfs instance on /mytmpfs which can allocate 10GB RAM/SWAP in 10240 inodes ...
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Securely wiping a file on a tmpfs

I have a script that decrypts some data to a tmpfs, the directory is secure (permissions), the machine's swap is encrypted (random key on boot) and when the script is done it does a 35 pass wipe (...
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Deleting files within the /tmp directory on an ubuntu machine

My Symfony website has just started to show the following error: ErrorException: Warning: session_start(): open (/tmp/sess_4h4kjh4ui4h478h48h44g02,O_RDWR) failed:No space left on device(28) in /var/...
1 vote
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Linux volatile user home areas

This is actually a 2 part question, one for design decisions, and the other a technical question: In our current network, we have Linux clients that authenticate against a server, and mount the user'...
4 votes
1 answer
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Where is terminal scroll back information stored (how does tmpfs work)?

While trying to test something unconnected, I launched an infinite loop on my terminator terminal emulator which printed a lot of data to STDOUT. After running it for a few minutes, I noticed that my /...
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How to find size of RAM cache use for ramfs, tmpfs

I'm wondering if there is any way to specify the size of RAM cache used to store ramfs, tmpfs? When I look at /proc/, I can't find anything about ramfs size.
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In linux is it possible to extend a ramdisk with a physcial drive in a logical volume?

I do not like how tmpfs behaves with swap and will allow memory to be exhausted before using the swap on physical disk (yes swappiness can be adjusted but it's still affecting the rest of the OS by ...
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how to tell chrome not use /run/shm or how to make /run/shm not mounted as tmpfs?

I have the problem with tmpfs and google chrome. When chrome runs, it uses /run/shm to keep some files like /run/shm/.com.google.Chrome.RnIWmb, the files are (deleted) but still open, that cause ...
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22 votes
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How to cleanup tmp folder safely on Linux

I use RAM for my tmpfs /tmp, 2GB, to be exact. Normally, this is enough but sometimes, processes create files in there and fail to cleanup after themselves. This can happen if they crash. I need to ...
3 votes
1 answer
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Mount TMPFS instead of ro /dev

I am working on a ARM-Based embedded system with a custom Debian Linux based on kernel 2.6.31. In the final system, the Root file system is stored as squashfs on flash. Now, the folder /dev is created ...
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5 votes
1 answer
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controling tmpfs memory usage

Any way to limit the amount of RAM used by tmpfs wihtout limiting the amount of swap? Most documentations says that tmpfs' size option will limit the total size of the tmpfs partition and later on ...
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2 votes
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tmpfs and debian - trash folder

I have created a tmpfs that remounts on boot and works as I had hoped for. My ram folder is here... /home/user/ramdrive/ While testing I noticed that when I delete files via the Debian GUI the files ...
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23 votes
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Why should I make a separate partition for /tmp?

Why should I make separate partitions for /tmp, /var and so on? I can see more drawbacks than benefits. One benefit is that I can use ext4 with journaling for /home and ext4 without journaling for ...
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How to make a good guess for the swap partition size when using tmpfs?

I have an SSD, so space is a scarce resource. I'd like to use up as little as possible for swap. In fact, I have spent the last year completely without a swap partition (the computer has 6 GB RAM). ...
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Does memory allocated to tmpfs free itself when needed by an application?

I have 8GB of RAM and 4GB is dedicated to the tmpfs on /dev/shm. There's nothing actually in /dev/shm, so I'm wondering, is this memory still available for applications to use? If I needed to use ...
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Have I successfully created an ramfs drive?

I thought I had created a ramfs drive, but when I type df -H all I get is following. Filesystem Size Used Avail Use% Mounted on /dev/sda5 69G 8.5G 57G 14% / /dev/...
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How do I unmount a tmpfs that is missing from /etc/mtab?

I have the following line in /etc/fstab: none /home/hydra/tmp tmpfs user,noauto,size=1000M,uid=1001,gid=1001 0 0 I can do mount ~/tmp as user hydra and it gets mounted ok. The only problem is ...
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How can I allow normal users to mount tmpfs under subdirectories of their home directory?

How can I allow normal users to mount a tmpfs under any subdirectory owned by them?
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How can I create consistent snapshots of tmpfs?

How can I create consistent snapshots of tmpfs or any RAM disks?
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Can I put /tmp and /var/log in a ramdisk on OS X?

For non-critical Linux systems, I often move things like /tmp and /var/log to tmpfs to save on some disk writing. I've been doing this for a year or so and if I ever need the logs across reboots, I ...
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9 votes
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Is using a Virtual PC on a RAM DISK super fast? (putting the .vhd file in a RAM DISK)

I wonder how or if any one tried to create a RAM DISK, and then put the 2GB (or sometimes 1.2GB) .vhd file into it, and then run the virtual PC using this image. It should be running super fast, as ...
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How tmpfs works in Debian?

I run df -h and found on my Debian Squeeze two tmpfs directory, tmpfs 1.5G 0 1.5G 0% /lib/init/rw tmpfs 1.5G 0 1.5G 0% /dev/shm Then, I added a line in ...
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/tmp broken: mount doesn't show anything

I'm on Ubuntu 9.04 and I've got the following problem: The folder /tmp normally has a tmpfs mounted in it. On one machine, this isn't the case anymore. I don't know what happened to have it that way. ...