초록 ▼

A data system has a data server and multiple clients. The data server organizes data according to a tree index structure, where memory pages used to store data are indexed by higher level index nodes in the tree structure. The index nodes are replicated and maintained locally at the clients. The dat

A data system has a data server and multiple clients. The data server organizes data according to a tree index structure, where memory pages used to store data are indexed by higher level index nodes in the tree structure. The index nodes are replicated and maintained locally at the clients. The data organization on the server is further characterized by use of indexed side links between data pages to provide side access traversal, such as a Pi-tree structure. During a search for a particular search space, a requesting client traverses its own index replica until reference is made to a data page at the server. If the request causes a data page split or otherwise changes the storage location of a particular search space, the server sends information back as part of the result message to the requesting client to update the tree index replica. However, no coherence messages are sent to other clients. Instead, the other clients learn of data page splits and other changes to the search space in their own time when they request the search space. When a second client tries to access a search space that has changed due to activity of the first client, the second client is initially directed to the data page it expects to contain the search space. The server then side traverses the data pages using the indexed side links until the actual data page with the search space is located. Each side traversal results in its index term being included in the result message. Such index terms, when received at the index replica, are posted in the replica maintained at the second client to update that index replica. Accordingly, replicas are maintained as a by product of their individual search requests, thereby removing the need for coherence or other coordination messages among all index replicas.

대표청구항 ▼

[ I claim:] [1.] In a data management computing system having data organized according to a tree index structure and supporting access to that data from multiple processing units through a distributed tree index architecture where at least a portion of the tree index is provided at the multiple proc

[ I claim:] [1.] In a data management computing system having data organized according to a tree index structure and supporting access to that data from multiple processing units through a distributed tree index architecture where at least a portion of the tree index is provided at the multiple processing units, a computer-implemented method for maintaining the tree indexes at the multiple processing units comprising the following steps:accessing the data from the processing units using their corresponding tree indexes;during said access by one of the processing units, changing a storage location of a particular search space; andupdating the tree index at said one processing unit without updating the tree indexes at others of the processing units.