This paper presents the transaction management in a highperformance distributed object storage system WAKASHI. Unlike othersystems that use centralized client/server architecture and otherconventional buffer management for distributed persistent objectmanagement, WAKASHI is based on symmetric peer-peer architecture andemploys memory-mapping and distributed shared virtual memory techniques.Several novel techniques of transaction management for WAKASHI aredeveloped. First, a multi-threaded transaction manager offers“multi-threaded connection” so that data control andtransaction operations can be performed in parallel manner. Secondly, aconcurrency control mechanism supports transparent page-level locks toreduce the complexity of user programs and locking overhead. Thirdly, a“compact commit” method is proposed to minimize thecommunication cost by reducing the amount of data and the number ofconnections. Fourthly, a redo-only recovery method is implemented by“shadowed cache” method to minimize the logging cost, and toallow fast recovery and system restart. Moreover, the system offers“hierarchical” control to support nested transactions. Aperformance evaluation by the OO7 benchmark is presented
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