Enabling swap accounting for Docker

This document (7016754) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 12 Service Pack 2
SUSE Linux Enterprise Server 12 Service Pack 3
SUSE Linux Enterprise Server 12 Service Pack 4
SUSE Linux Enterprise Server 12 Service Pack 5
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server 15 Service Pack 1
SUSE Linux Enterprise Server 15 Service Pack 2
SUSE Linux Enterprise Server 15 Service Pack 3

Situation

The following warning may be generated when the Docker host kernel does not take swap accounting into consideration:

WARNING: Your kernel does not support cgroup swap limit.
WARNING: Your kernel does not support swap limit capabilities. Limitation discarded.

Resolution

To remove this warning message perform the following steps:

Start YaST, and select System > Boot Loader
Click 'Kernel Parameters'
Enter the following strings inside of the “Optional Kernel Command Line Parameter”:
swapaccount=1
Press the OK button
Reboot your machine

Alternatively:

edit the /etc/default/grub file
Add the following string inside of the GRUB_CMDLINE_LINUX_DEFAULT variable:
swapaccount=1
Save the change
Run: “sudo update-bootloader –refresh”
Reboot your machine

Additional Information

The swap warnings are not seen on SLES15 SP4

Cgroups v2 are supported starting with SLES15 SP2

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.