Parallel database

A parallel database system seeks to improve performance through parallelization of various operations, such as loading data, building indexes and evaluating queries. Although data may be stored in a distributed fashion, the distribution is governed solely by performance considerations. Parallel databases improve processing and input/output speeds by using multiple CPUs and di, where multiple processors share the main memory space, as well as mass storage (e.g. hard disk drives).

• Shared disk architecture, where each node has its own main memory, but all nodes share mass storage, usually a storage area network. In practice, each node usually also has multiple processors.
• Shared nothing architecture, where each node has its own mass storage as well as main memory.

The other architecture group is called hybrid architecture, which includes:

• Non-Uniform Memory Architecture (NUMA), which involves the Non-Uniform Memory Access.
• Cluster (shared nothing + shared disk: SAN/NAS), which is formed by a group of connected computers.

References

Communications of the ACM: Parallel database systems: the future of high performance database systems