Storage Management Of Main Memory Database(MMDB)

With the development of science and technology,requirement of new application and maturity of objective condition(increase of memory capacity) makes the MMDB(Main Memory Database) came into being. MMDB put the work version of database in memory, so I/O of disk will not be bottleneck any more, the goal of designing MMDB will be transferred to efficiently employing CPU and main memory. As the storage management module is the core of the MMDB, the strategies of storage management directly related to the performance of MMDB system.This paper first Introduced the concept of MMDB and the research status at home and abroad, then analyze the key technologies of storage management, including the storage layer structure of MMDB, the management of memory space, the Organizational structure of MMDB, the storage model of MMDB, the storage structureof MMDB, etc.On the basis of a thorough understanding the key technologies used in storage management of MMDB, the realization of storage management module of Main Memory Database cachDB is given, mainly describe the strategie used in the storage management of cachDB, as a improvement of"memory pool strategy", cachDB gives a solution based on memory page for the management of memory. Trough these, cachDB could find and distribute the available memory space quickly and ensure the utilization of memory space. This paper also propose a storage structure that store the combination of index and record, thus the insert operation of MMDB is simplified and the utilization of memory is improved.the test and analysis tells us that cachDB could find and distribut available memory quickly(about 50M Byte/second), and could make good use of memory space of MMDB. Test also proved that the combination of index and record could simplify the operation of MMDB , the insertion rate is increased by 20% to 25% than before, and the MMDB consumed less memory than before, the utilization of the memory is improved.