Ubuntu/swap - Revision history

Woozle at 14:12, 2 June 2025

2025-06-02T14:12:47Z

← Older revision		Revision as of 14:12, 2 June 2025
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	Commands:		Commands:
	* {{l/cmd\|swapon}} --show		* <code>{{l/cmd\|swapon}} --show</code>
	** Confirms the swap-file status (default is currently 2 gigabytes)		** Confirms the swap-file status (default is currently 2 gigabytes)
	* sudo {{l/cmd\|fallocate}} -l 4G /swap4G		* <code>sudo {{l/cmd\|fallocate}} -l 4G /swap4G</code>
	** 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		* <code>sudo {{l/cmd\|chmod}} 0600 /swap4G</code>
	** Not required, but reduces warning messages and possible security holes.		** Not required, but reduces warning messages and possible security holes.
	* sudo mkswap /swap4G		* <code>sudo mkswap /swap4G</code>
	** Mark the new file as a swapfile.		** Mark the new file as a swapfile.
	* sudo swapon /swap4G		* <code>sudo swapon /swap4G</code>
	** Tell the swap system to use the new file.		** Tell the swap system to use the new file.
	* sudo swapoff /swapfile		* <code>sudo swapoff /swapfile</code>
	** Turn off usage of the given swapfile (<code>/swapfile</code> is the name of the default) -- but make sure you've got enough RAM free first, or have set up another swapfile!		** Turn off usage of the given swapfile (<code>/swapfile</code> 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.		** This will take some time, depending on how full this swapfile is.

Woozle at 19:01, 3 December 2022

2022-12-03T19:01:09Z

← Older revision		Revision as of 19:01, 3 December 2022
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	** 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.
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	** 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]

Woozle at 18:49, 3 December 2022

2022-12-03T18:49:10Z

← Older revision		Revision as of 18:49, 3 December 2022
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	* sudo swapoff /swapfile		* sudo swapoff /swapfile
	** Turn off usage of the given swapfile (<code>/swapfile</code> is the name of the default) -- but make sure you've got enough RAM free first, or have set up another swapfile!		** Turn off usage of the given swapfile (<code>/swapfile</code> 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.		** Yes, you can have two swapfiles in use simultaneously.
	==Notes==		==Notes==

Woozle: Created page with "==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 {{l/cmd..."

2022-12-03T18:44:40Z

Created page with "==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 {{l/cmd..."

New page

==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 {{l/cmd|fdisk}}.

Commands:
* {{l/cmd|swapon}} --show
** Confirms the swap-file status (default is currently 2 gigabytes)
* sudo {{l/cmd|fallocate}} -l 4G /swap4G
** 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.
* 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 (<code>/swapfile</code> is the name of the default) -- but make sure you've got enough RAM free first, or have set up another swapfile!
** Yes, you can have two swapfiles in use simultaneously.
==Notes==
* [https://www.tldp.org/HOWTO/Partition/setting_up_swap.html Linux Partition HOWTO: 9. Setting Up Swap Space]
** '''2020-02-11''' [https://linuxhandbook.com/increase-swap-ubuntu/ How to Increase Swap Size on Ubuntu] (using the new [https://help.ubuntu.com/community/SwapFaq 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.
* upgrade command for 16.04 LTS: <code>do-release-upgrade</code>