Migrating from cgroup v1 to cgroup v2

Learn how to migrate from cgroup v1 to cgroup v2. You must migrate from cgroup v1 to cgroup v2 for managing the cluster resources using cgroup v2 resource allocation configuration parameters.

Upgrade Cloudera Manager to Cloudera Manager 7.13.1 (minimum Cloudera Manager version which supports cgroup v2). For upgrading Cloudera Manager, see Upgrading Cloudera Manager 7.

important

For the users using RHEL 9.x with Cloudera Manager version lower than 7.13.1, must disable cgroup v2 if already enabled before upgrading to Cloudera Manager 7.13.1 version as cgroup v2 is not supported with Cloudera Manager version lower than 7.13.1.
Optional: If you want to provide a custom path in the config.ini file for cgroup V2, ensure you add the following parameter to the config.ini file under the [Cgroup_Paths] section after performing a CM upgrade:
```
controllers_cgroup_path=/
```
In case of fresh installation, by default, this custom path is available in the config.ini file under the [Cgroup_Paths] section and hence there is no need to add a custom path in the config.ini file for cgroup V2.
Upgrade CDP Runtime to CDP 7.3.1 (minimum CDP Runtime version). For upgrading CDP Runtime, see Upgrading a Cloudera Runtime Cluster.
Disable the Enable Cgroup-based Resource Management property for cgroup v1 by performing the following steps:
1. On the Cloudera Manager UI, navigate to Hosts > Hosts Configuration.
2. Select Category > Resource Management.
3. Clear the Enable Cgroup-based Resource Management checkbox.
4. Click Save Changes.
Upgrade OS to RHEL 9.

important

During major OS upgrades, while upgrading from Redhat 8 (defaults to cgroup v1) to Redhat 9 (defaults to cgroup v2), the resource configurations will not be automatically transferred such as value of Cgroup V1 CPU Shares will not be populated in Cgroup V2 CPU Weight. Also, the controller files inside the process directories will be created under cgroups root path with default values.
Enable the Enable Cgroup-based Resource Management property for cgroup v2 by performing the following steps:
1. On the Cloudera Manager UI, navigate to Hosts > Hosts Configuration.
2. Select Category > Resource Management.
3. Select the Enable Cgroup-based Resource Management checkbox.
4. Click Save Changes.
important
- If you are setting cgroup v1 parameter values manually, then you should now set cgroup v2 parameter values manually (performing conversion of values manually) and restart the services using cgroups.
  
  Note that Cloudera Manager UI will have old values under cgroup v1 parameters which you can use as a reference to re-configure the values in the case of cgroup v2.
- If you are using the Static Service Pools wizard to allocate resources, then you should run the Static Service Pools wizard again with the necessary percentage settings to generate cgroup v2 parameter values.
Restart the services that are using cgroups.