437 Queue Rate Limiting 719e50f5

Rate Limit Queue Execution

Set rate limits on a queue to control how many workflows start in a given period. Rate limits are global across all DBOS processes.

Incorrect (no rate limiting):

queue := dbos.NewWorkflowQueue(ctx, "llm_tasks")
// Could send hundreds of requests per second to a rate-limited API

Correct (rate-limited queue):

queue := dbos.NewWorkflowQueue(ctx, "llm_tasks",
	dbos.WithRateLimiter(&dbos.RateLimiter{
		Limit:  50,
		Period: 30 * time.Second,
	}),
)

This queue starts at most 50 workflows per 30 seconds.

Combining rate limiting with concurrency:

// At most 5 concurrent and 50 per 30 seconds
queue := dbos.NewWorkflowQueue(ctx, "api_tasks",
	dbos.WithWorkerConcurrency(5),
	dbos.WithRateLimiter(&dbos.RateLimiter{
		Limit:  50,
		Period: 30 * time.Second,
	}),
)

Common use cases:

• LLM API rate limiting (OpenAI, Anthropic, etc.)
• Third-party API throttling
• Preventing database overload

Reference: Rate Limiting