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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Why is the filesystem larger than logical volume?
On the machine, there is a logical volume /dev/lvm/tmp of size 500MiB with the same size partition /dev/mapper/tmp that is mounted on /tmp.
Checking the logical volume:
# lvdisplay /dev/lvm/tmp
--- ...
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Build Docker image on tmpfs
I have a Dockerfile that change file permissions to various folders, one of that is a node_modules
RUN chown -R 0:0 . ...
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Why does booting tmpfs overlayroot filesystem on read-only disk boot to emergency mode?
I enabled tmpfs overlayroot running following.
$ sudo sed -i 's/overlayroot=""/overlayroot="tmpfs"/g' /etc/overlayroot.conf
After rebooting, Ubuntu boots as read-only and ...
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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)
...
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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 ...
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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 ...
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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 ...
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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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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/...
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