A technique is described for guaranteeing recovery in a computer system comprising of recovery contracts with a plurality of obligations for a message exchange between a first component and a second component. Three forms of contract are described, governing interactions between three types of components. Each contract is bilateral, i.e. between a first component and a second component. The first and second components have mutual agreement on when the contract will be released to facilitate log truncation, and independent and/or autonomous recovery. The use of persistent and transactional components and the requirements for ensuring that it is possible to replay the components in a deterministic fashion, can result in a high cost or overhead in logging of nondeterministic events, including component interactions. An appreciation that this requirement may result in overly pessimistic logging has led to the definition of three additional component types, a functional component, a subordinate component and a read-only component.

 
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< Selective automated power cycling of faulty disk in intelligent disk array enclosure for error recovery

> Methods and apparatus for parsing Extensible Markup Language (XML) data streams

> Default locality selection for memory objects based on determining the type of a particular memory object

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