When deploying apps with Docker images under the 'Routinely clean up Diego Cell disk space' configuration option, the ephemeral disk space continues to increase until it is full

Products

• VMware Tanzu Application Service for VMs

Issue/Introduction

If you are using ‘Routinely clean up Diego Cell disk space’ option and primarily runniing both Docker images and buildpack-based apps. you might notice that the ephemeral disk space continues to increase until it is full.

Environment

Product Version: 2.11

Resolution

The background:

Routinely clean up Diego Cell disk space: This option is designed to trigger a disk cleanup on the Diego Cell whenever a new container is created, applicable to both buildpack-based and Docker applications. Unfortunately, a bug has been present since 2018 that affects the cleanup process at the time of container creation, and it may not be feasible to fix this issue. If routine garbage collection cannot be reliably reintroduced, the 'Routinely clean up Diego Cell disk space' configuration option may be removed.

Clean up disk space once usage fills disk: This option configures the Diego Cell to initiate a disk cleanup only when the disk usage approaches the limit reserved for other jobs.

 

To prevent the ephemeral disks from filling up entirely, you should configure the following:

App Containers → Docker images disk cleanup scheduling on Diego Cell VMs → Clean up disk space once usage fills disk

You should select Clean up disk space once usage fills disk following the docs in Configuring Diego Cell disk cleanup scheduling to help choose a different reserve than the default, only if you have bosh addons that require space on the ephemeral disk.