Production Schema Caching and Metadata Persistence Limits

In CakePHP, metadata caching is typically disabled during development to allow for rapid schema changes, but it is a documented requirement for production environments to prevent redundant DESCRIBE queries on every request.

When migrating from a local environment to production, the application relies on the tmp directory to store these cached schema files. If the production environment implements stricter filesystem permissions or uses a read-only filesystem, the ORM may fail to persist the metadata cache despite the configuration being set to enabled.

This creates a discrepancy where the application functions locally but suffers significant performance degradation or runtime errors in production due to the inability to write to the cache store.

• How does CakePHP handle the fallback mechanism when the configured metadata cache engine is unreachable or read-only in production?
• What are the specific constraints for verifying that schema caching is active without relying on manual filesystem inspection of the tmp folder?