4 ms·

In addition to /var, tmpfs should also be used for /tmp and similar. That should lengthen the SD card's lifetime immensely.

diggan 3y ago
Isn't this (tmpfs for /tmp) the default setup for most OSes, and surely raspberry's homegrown OS too?
- tyingq 3y ago
  It seems it is not the default for Raspbian.
  - diggan 3y ago
    TIL! One would think if any distribution had it by default, it would have been Raspbian.
    - tyingq 3y ago
      Maybe left off since some of the models have very little memory to spare for a ramdisk?
- iforgotpassword 3y ago
  I think all the usual desktop distros don't use tmpfs for either by default. I don't see the benefit in this with modern hardware.
  - gkbrk 3y ago
    Arch uses tmpfs for /tmp.
    - Macha 3y ago
      Arch has you set up your own fstab so pushes the choice to the user?
      - GrumpySloth 3y ago
        During installation the guide tells you to run a program, which generates an fstab based on current mounts. So by default it will configure /tmp the same way it’s configured in the live cd.
      - gabrielhidasy 3y ago
        Actually the installation guide for arch asks you to use `genfstab -U /mnt >> /mnt/etc/fstab` which basically copies over whatever was mounted at the live environment (taking off the /mnt), I'm pretty sure tmpfs for /tmp was there by default last time I installed.
  - lillecarl 3y ago
    I ran out of space on NixOS with tmpfs, they run all builds in /tmp so my swap ran out.
    - bonzini 3y ago
      They should use /var/tmp instead.
  - zitsarethecure 3y ago
    Fedora uses tmpfs for /tmp. I think it still makes a lot of sense to use tmpfs for a heavily written-to transient file system.
- marcosdumay 3y ago
  A long time ago, it used to be. It doesn't seem to be now, and I don't have any idea why the distros changed. (Maybe it's due to the mv semantics? But I though people considered the idea of creating a file in /tmp and then renaming it to be bad instead.) In fact, I didn't notice the change until now.
  - adrian_b 3y ago
    Copying or moving through tmpfs loses silently some file metadata, e.g. extended attributes or high-resolution filestamps. Copying through /tmp is a frequently used method for transferring files between users on a multi-user computer. It is said that the Linux kernel will include soon an improved version of tmpfs, which will allow user extended attributes, within certain limitations. When this will happen, one of the most annoying misfeatures of tmpfs that has persisted for much too many years will finally be gone away.
- LtWorf 3y ago
  Not the default in debian, because of low memory devices such as rpi.
- rootbear 3y ago
  If I had to guess, I would assume they chose not to use tmpfs because the earlier Pis had very limited RAM. With a 4GB or 8GB pi 4 or 5 this should not be a problem.
- Too 3y ago
  Surprisingly often not! Be careful to check inside your docker containers also. It can end up different. Here is a good article btw, with someone advocating for moving to tmpfs https://ubuntu.com/blog/data-driven-analysis-tmp-on-tmpfs https://ubuntu.com/blog/data-driven-analysis-tmp-on-tmpfs
blacklion 3y ago
Anything transient writable must be in memfs/tmpfs/how it is mamre im your OS, of course. Logs to log server, if system needs non-volatile writable storage — NFS or second storage device, depending on requirements. Of course, it is too much hassle for single such system (but I started to use it from very beginning out of curiosity) but uf you have many single-task small devices it is very convenient.

diggan 3y ago

Isn't this (tmpfs for /tmp) the default setup for most OSes, and surely raspberry's homegrown OS too?

tyingq 3y ago
It seems it is not the default for Raspbian.
- diggan 3y ago
  TIL! One would think if any distribution had it by default, it would have been Raspbian.
  - tyingq 3y ago
    Maybe left off since some of the models have very little memory to spare for a ramdisk?
iforgotpassword 3y ago
I think all the usual desktop distros don't use tmpfs for either by default. I don't see the benefit in this with modern hardware.
- gkbrk 3y ago
  Arch uses tmpfs for /tmp.
  - Macha 3y ago
    Arch has you set up your own fstab so pushes the choice to the user?
    - GrumpySloth 3y ago
      During installation the guide tells you to run a program, which generates an fstab based on current mounts. So by default it will configure /tmp the same way it’s configured in the live cd.
    - gabrielhidasy 3y ago
      Actually the installation guide for arch asks you to use `genfstab -U /mnt >> /mnt/etc/fstab` which basically copies over whatever was mounted at the live environment (taking off the /mnt), I'm pretty sure tmpfs for /tmp was there by default last time I installed.
- lillecarl 3y ago
  I ran out of space on NixOS with tmpfs, they run all builds in /tmp so my swap ran out.
  - bonzini 3y ago
    They should use /var/tmp instead.
- zitsarethecure 3y ago
  Fedora uses tmpfs for /tmp. I think it still makes a lot of sense to use tmpfs for a heavily written-to transient file system.
marcosdumay 3y ago
A long time ago, it used to be. It doesn't seem to be now, and I don't have any idea why the distros changed. (Maybe it's due to the mv semantics? But I though people considered the idea of creating a file in /tmp and then renaming it to be bad instead.) In fact, I didn't notice the change until now.
- adrian_b 3y ago
  Copying or moving through tmpfs loses silently some file metadata, e.g. extended attributes or high-resolution filestamps. Copying through /tmp is a frequently used method for transferring files between users on a multi-user computer. It is said that the Linux kernel will include soon an improved version of tmpfs, which will allow user extended attributes, within certain limitations. When this will happen, one of the most annoying misfeatures of tmpfs that has persisted for much too many years will finally be gone away.
LtWorf 3y ago
Not the default in debian, because of low memory devices such as rpi.
rootbear 3y ago
If I had to guess, I would assume they chose not to use tmpfs because the earlier Pis had very limited RAM. With a 4GB or 8GB pi 4 or 5 this should not be a problem.
Too 3y ago
Surprisingly often not! Be careful to check inside your docker containers also. It can end up different. Here is a good article btw, with someone advocating for moving to tmpfs https://ubuntu.com/blog/data-driven-analysis-tmp-on-tmpfs https://ubuntu.com/blog/data-driven-analysis-tmp-on-tmpfs

blacklion 3y ago

Anything transient writable must be in memfs/tmpfs/how it is mamre im your OS, of course. Logs to log server, if system needs non-volatile writable storage — NFS or second storage device, depending on requirements. Of course, it is too much hassle for single such system (but I started to use it from very beginning out of curiosity) but uf you have many single-task small devices it is very convenient.