RetryPolicy

A retryPolicy is a configuration that governs how a system responds to transient failures by retrying the operation. It is commonly applied to network calls, remote services, and other operations where intermittent errors may recur.

Key parameters typically include the maximum number of attempts, the initial delay between attempts, a backoff strategy (fixed, exponential, or jittered), the maximum delay, a total timeout, and the set of retryable errors or status codes. An idempotency requirement may also be specified to ensure safety when an operation is retried.

Backoff strategies help balance speed and system load. Fixed backoff uses a constant wait between retries; exponential backoff grows the delay with each attempt; jitter adds randomness to minimize synchronized retries. Policies may cap delays to avoid excessively long waits.

Design considerations include ensuring the operation is safe to retry (idempotent or compensating actions), distinguishing transient from permanent failures, and combining retries with circuit breakers to prevent cascading outages. Retries should honor timeouts and avoid creating side effects or violating external constraints.

In practice, retryPolicy appears in HTTP clients, RPC stubs, message processors, and batch jobs, often as part of resilience libraries. It is usually paired with timeouts and observability to monitor retry rates and outcomes. Related concepts include backoff strategies, circuit breakers, idempotency, and dead-letter handling.