Liveupdate

Liveupdate refers to methods and systems that allow software to receive and apply updates while running, avoiding restart or downtime. It encompasses hot patching, dynamic module replacement, and resource reloading, enabling patches, configuration changes, or asset updates to take effect without interrupting operation.

A typical liveupdate architecture includes an update server that distributes a manifest and delta payloads, signed packages, and release notes to clients. Clients verify signatures and integrity with checksums, stage changes in a safe area, and perform an atomic switch to the new state. Rollback mechanisms are important for recovery if the update causes issues. Updates can be delivered on a pull basis, with clients fetching updates, or push-based, where a service triggers updates. Some implementations use streaming, in-app scripting, or dynamic loading to apply changes without a restart.

Common use cases include operating system live patches, cloud services updating microservices in place, game engines delivering patches without downtime, and web applications applying feature toggles or content updates. Mobile apps may use incremental updates to reduce download size, while large-scale deployments favor canary or blue-green rollout patterns to minimize risk.

Key challenges involve maintaining security and integrity, ensuring compatibility with the current state, and handling partial or failed updates without corrupting the system. Performance overhead, memory management, and potential side effects from live patches require careful design, testing, and observability.

See also: dynamic software updating, hot patching, over-the-air updates, patch management, feature flags, and atomic commits.