Difference between revisions of "Ubuntu/swap"
< Ubuntu
Jump to navigation
Jump to search
Line 8: | Line 8: | ||
** creates a new swapfile-compatible 4 gigabyte file named <code>/swap4G</code> | ** creates a new swapfile-compatible 4 gigabyte file named <code>/swap4G</code> | ||
** Regardless of what's implied by the tldp.org instructions, you can do this ''before'' disabling the old swapfile as long as you give it a different name. | ** Regardless of what's implied by the tldp.org instructions, you can do this ''before'' disabling the old swapfile as long as you give it a different name. | ||
+ | * sudo {{l/cmd|chmod}} 0600 /swap4G | ||
+ | ** Not required, but reduces warning messages and possible security holes. | ||
* sudo mkswap /swap4G | * sudo mkswap /swap4G | ||
** Mark the new file as a swapfile. | ** Mark the new file as a swapfile. | ||
Line 16: | Line 18: | ||
** This will take some time, depending on how full this swapfile is. | ** This will take some time, depending on how full this swapfile is. | ||
** Yes, you can have two swapfiles in use simultaneously. | ** Yes, you can have two swapfiles in use simultaneously. | ||
+ | |||
+ | Then edit {{l/ke/file|/etc/fstab}} to change the name of the swapfile you want to use. You can delete the old swapfile either before or after that, but safest to do it after. | ||
==Notes== | ==Notes== | ||
* [https://www.tldp.org/HOWTO/Partition/setting_up_swap.html Linux Partition HOWTO: 9. Setting Up Swap Space] | * [https://www.tldp.org/HOWTO/Partition/setting_up_swap.html Linux Partition HOWTO: 9. Setting Up Swap Space] |
Latest revision as of 19:01, 3 December 2022
About
Newer versions of Ubuntu use a regular(ish) file for swap, rather than a partition -- so resizing it is now possible without rebooting or mucking around with fdisk.
Commands:
- swapon --show
- Confirms the swap-file status (default is currently 2 gigabytes)
- sudo fallocate -l 4G /swap4G
- creates a new swapfile-compatible 4 gigabyte file named
/swap4G
- Regardless of what's implied by the tldp.org instructions, you can do this before disabling the old swapfile as long as you give it a different name.
- creates a new swapfile-compatible 4 gigabyte file named
- sudo chmod 0600 /swap4G
- Not required, but reduces warning messages and possible security holes.
- sudo mkswap /swap4G
- Mark the new file as a swapfile.
- sudo swapon /swap4G
- Tell the swap system to use the new file.
- sudo swapoff /swapfile
- Turn off usage of the given swapfile (
/swapfile
is the name of the default) -- but make sure you've got enough RAM free first, or have set up another swapfile! - This will take some time, depending on how full this swapfile is.
- Yes, you can have two swapfiles in use simultaneously.
- Turn off usage of the given swapfile (
Then edit /etc/fstab
to change the name of the swapfile you want to use. You can delete the old swapfile either before or after that, but safest to do it after.
Notes
- Linux Partition HOWTO: 9. Setting Up Swap Space
- 2020-02-11 How to Increase Swap Size on Ubuntu (using the new swapfile instead of partitioning)
- Note that you have to edit fstab for the change to persist after reboot.
- Also, it's not necessary to do swapoff except to stop using a given swapfile. You can add a new swapfile at any point, and the system will use more than one swapfile concurrently.
- 2020-02-11 How to Increase Swap Size on Ubuntu (using the new swapfile instead of partitioning)
- upgrade command for 16.04 LTS:
do-release-upgrade