Explanation
Deleting an Image
When you no longer need an old image or you simply want to clean up the list of image tags in a repository, you can delete images from Oracle Cloud Infrastructure Registry.
Your permissions control the images in Oracle Cloud Infrastructure Registry that you can delete. You can delete images from repositories you've created, and from repositories that the groups to which you belong have been granted accessby identity policies. If you belong to the Administrators group, you can delete images from any repository in the tenancy.
Note that as well deleting individual images , you can set up image retention policies to delete images automatically based on selection criteria you specify (see Retaining and Deleting Images Using Retention Policies).
Note:
In each region in a tenancy, there's a global image retention policy. The global image retention policy's default selection criteria retain all images so that no images are automaticallydeleted. However, you can change the global image retention policy so that images are deleted if they meet the criteria you specify. A region's global image retention policy applies to all repositories in the region, unless it is explicitly overridden byone or more custom image retention policies.
You can set up custom image retention policies to override the global image retention policy with different criteria for specific repositories in a region. Having created a custom image retention policy, you apply the custom retention policy to a repository by adding the repository to the policy. The global image retention policy no longer applies to repositories that you add to a custom retention policy.
https://docs.cloud.oracle.com/en-us/iaas/Content/Registry/Tasks/registrymanagingimageretention.htm#:~:text=In