Storage, persistent network

The Data Persistence Layer can be a thick layer that resides in the application middleware or a thin layer in the application middleware combined with some stored procedures in the database. The former makes the Data Persistence Layer independent of the underline RDBMS that is being used. The latter provides better performance because the number of network calls can be reduced. Either way, a wed-defined interface between the Business Layer and the Data Storage Layer is the key. 

There are two principal ways to provide persistent storage in a parallel computer each node may have its own local disk, or a common storage device may be shared by all nodes and accessed via a network. The nodes in a parallel... 

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