CloudFlow provides two execution modes -- standard and express (also known as quick mode) -- that differ in duration limits, throughput, execution guarantees, and observability. Choose the mode that fits your workload: standard mode for long-running, durable workflows with full execution history; express mode for high-throughput, low-latency orchestration that completes within seconds.
Choose a mode
Use the following table to match your workload requirements to the right mode.
| Requirement | Recommended mode |
|---|---|
| Execution lasts longer than 5 minutes | Standard mode |
Workflow requires callback-based integration (WaitForCustomCallback, WaitForSystemCallback) | Standard mode |
| Full execution history with API-based querying | Standard mode |
| High-throughput, low-latency orchestration (> 100 QPS) | Express mode |
| Microservices API orchestration or glue-layer APIs | Express mode |
| Stream processing | Express mode |
Feature comparison
| Feature | Standard mode | Express mode |
|---|---|---|
| Maximum execution duration | 1 year | 5 minutes |
| Execution model | Asynchronous. Each step's status is persisted, enabling long-running workflows to resume after interruptions. | Synchronous. Returns the result upon completion. |
| Delivery guarantee | At-least-once. Data is never lost, but a step may run more than once under certain conditions. | Retries automatically on system errors. Configure client-side retries based on your business requirements. |
| Flow start rate | 100 QPS | 1,000 QPS by default. To request a higher rate, submit a ticket. |
| Concurrency | 10,000 | 10,000 by default. To request higher concurrency, submit a ticket. |
| Execution history | Full execution history recorded. Query and list executions through API operations. | Simple Log Service queries planned. During public preview, query executions through API operations only. |
| Integration modes | RequestComplete, WaitForCustomCallback, WaitForSystemCallback. See Integration modes. | RequestComplete only. |
| Service integration | All integration methods supported. See Service integration overview. | All integration methods supported. See Service integration overview. |
Integration mode details
Standard mode supports three integration modes. Express mode supports only RequestComplete.
| Integration mode | Description | Supported modes |
|---|---|---|
RequestComplete | The workflow step completes when the integrated service returns a response. | Standard, Express |
WaitForCustomCallback | The workflow step pauses until an external system sends a callback. | Standard only |
WaitForSystemCallback | The workflow step pauses until the integrated service sends a system callback upon task completion. | Standard only |
If your workflow requires callback-based patterns, use standard mode.