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Horizontal Partitioning

If you have a large flat namespace, you can improve performance by partitioning the namespace, so that different DSAs each serve different parts of the same level of namespace. In CA Directory, horizontal partitioning is a method of doing this.

A horizontal partitioning setup consists of a router DSA and a number of data DSAs.

The router and its data DSAs serve the namespace. The clients do not know which data DSA stores the data for each part of the namespace.

The namespace data is partitioned among the data DSAs by hashing the RDN of each entry. Each data DSA is distinguished by the hash value assigned to the prefix. Apart from the hash value, the prefix specification is identical for all the DSAs in the set.