The dependency graph is a summary of the manifest and lock files stored in a repository. For each repository, it shows dependencies, that is, the ecosystems and packages it depends on. GitHub AE does not calculate information about dependents, the repositories and packages that depend on a repository.
For more information, see "About the dependency graph."
When the dependency graph is first enabled, any manifest and lock files for supported ecosystems are parsed immediately. The graph is usually populated within minutes but this may take longer for repositories with many dependencies. Once enabled, the graph is automatically updated with every push to the repository.