Hello @Marvin, why does a Push Work Pool not need a Worker? How is that possible?

A Push Work Pool does not need a Worker because it is designed to submit flow runs directly to serverless infrastructure. In this setup, the work pool itself handles the delivery of work to the execution environment, which is typically in the form of serverless functions that are invoked to process the work items. Work pools in Prefect can be categorized by the delivery method of work to the execution environment: 1. Pull Work Pools: These require workers or agents to poll the work pool for flow runs to execute. 2. Push Work Pools: These can submit runs directly to the serverless infrastructure without the need for a worker to poll for tasks. This decouples the orchestration environment from individual worker management, relying on the serverless platform's native ability to scale and manage execution based on the work submitted by the push work pool. Serverless platforms like AWS Lambda, Azure Functions, or Google Cloud Functions are typically used in conjunction with push work pools to enable this kind of execution. For more detailed information, you can read directly from the document.

@Marvin How does a Push Work Pool poll and know when a run is completed or failed or running?

A Push Work Pool, when used with serverless infrastructure providers such as Google Cloud Run, Azure Container Instances, and AWS ECS, does not rely on a traditional polling mechanism by the worker or agent to know when a run is completed, failed, or running. Instead, the serverless infrastructure is responsible for executing the workflow and can update the status of the run (completed, failed, or running) back to the orchestration environment. This allows for a loosely-coupled architecture where the work pool submits the run and the serverless platform manages the lifecycle of the run, including scaling the infrastructure as needed. The interaction between the Push Work Pool and the serverless infrastructure can be thought of as similar to a pub/sub or message-based system. In this model, the work pool can be seen as a "topic" that helps coordinate deployments with the infrastructure, but it does not actively poll for run statuses. Instead, status updates are typically pushed back by the serverless platform to the Prefect orchestration environment, which then reflects the latest run statuses. For more information on how this specifically works with Prefect, you may want to consult the Prefect documentation or forums for integrations with various serverless platforms and the specifics of status updates.

oh duh

Someone might choose to use a Pull Work Pool over a Push Work Pool for several reasons: 1. Control and Flexibility: With Pull Work Pools, workers or agents actively poll for available runs and manage the execution of those runs. This gives users more control over the execution environment and the ability to fine-tune their workflows and resource usage. 2. Custom Execution Environments: Pull Work Pools are suitable for those who have specific requirements for the execution environment that are not easily met by serverless offerings. Users can set up custom infrastructure that aligns with their security, compliance, and operational needs. 3. Persistent Infrastructure: Serverless architectures typically require tasks to be stateless and have short execution times. In scenarios where workflows require persistent infrastructure, such as long-running workloads or workflows that need to maintain state between runs, a Pull Work Pool would be more appropriate. 4. Cost Considerations: Managed serverless solutions often come with a cost premium for the convenience and scalability they offer. If cost optimization is a concern, and workflows can be efficiently run on self-managed infrastructure, the Pull Work Pool might be more cost-effective. 5. Compatibility with Legacy Systems: Some workflows might need to integrate with legacy systems that aren't compatible with serverless architectures. In such cases, workers pulling from a Pull Work Pool can be customized to interact with those systems. 6. Debugging and Development: During development or debugging, it can be helpful to have workers that pull jobs so that developers can more easily simulate and monitor the execution of flow runs in a local or development environment. In summary, the decision to use a Pull Work Pool is often driven by the desire for more control over the workflow's execution, the need for custom or legacy system integration, cost considerations, and development convenience.

@Jack P you need to trust prefect with your cloud platform credentials for push work pools. running your own worker, you don't