- Most standard App Engine apps use queue.yaml to configure queues in the App Engine Task Queue service.
- For Java apps, the queue.xml file is used instead.
- The Cloud Tasks API provides an App Engine-independent interface to the App Engine Task Queue service.
- Cloud Tasks API provides the ability to manage queues, including doing so via the console or the gcloud command.
- Queues that are created by Cloud Tasks API are accessible from the App Engine SDK and vice versa.
- To maintain compatibility, it is possible to use the configuration file used by the App Engine SDK, queue.yaml, to create and configure queues used via the Cloud Tasks API.
- Mixing configuration via file with configuration via the Cloud Tasks API can produce unexpected consequences.
- It is strongly recommended to use either the configuration file method or the Cloud Tasks API to configure queues, but not both.
- If new to Cloud Tasks or App Engine, use the Cloud Tasks API exclusively to manage queues and avoid the use of queue.yaml and queue.xml altogether.
- Cloud Tasks queue management methods give users more choice in creating, updating, and deleting queues.
- Inspect project's Admin Activity audit logs to retrieve the history of queue configuration changes including queue creations, updates, and deletions:
- If queue.yaml is mixed with Cloud Tasks queue management methods, uploading a queue.yaml file might accidentally disable a queue created through the Cloud Tasks API.
- Resuming many high-QPS queues at the same time can lead to target overloading.
- If resuming high-QPS queues, follow the 500/50/5 pattern
- If queue.yaml is used to create queues, by default, create a maximum of 100 queues.
- Queues created using the Cloud Tasks API have a default maximum of 1,000 queues.