Recovery manner of the database from fault of the shared storage in the multiple computer data shared systems

摘要

In a multi-system data sharing complex 10, 12, 13, a database system can write updated pages to a shared electronic store 16, for a fast write. Other database systems can obtain pages written to the shared store for further modification without the pages first being written to stable storage 14, 15. However, pages are eventually written to the stable storage in a castout process. Recovery of a database from failure of the shared store is bounded by determination of a recovery boundary which, when applied to the union of database system transaction logs, establishes a point in front of which are found log records of modifications to pages which were in the shared store when it failed. These log records are applied to page versions obtained from stable storage to recover from failure of the shared store. IMAGE