Dali: A high performance main memory storage manager

Performance needs of many database appli-cations dictate that the entire database be stored in main memory. The Dali system is a main memory storage manager designed to provide the persistence, availability and safety guarantees one typically expects from a disk-resident database, while at the same time pro-viding very high performance by virtue of be-ing tuned to support in-memory data. Dali follows the philosophy of treating all data, in-cluding system data, uniformly as database files that can be memory mapped and directly accessed/updated by user processes. Direct access provides high performance; slower, but more secure, access is also provided through the use of a server process. Various features of Dali can be tailored to the needs of an ap-plication to achieve high performance- for example, concurrency control and logging can be turned off if not desired, which enables Dali to efficiently support applications that re-quire non-persistent memory resident data to be shared by multiple processes. Both object-oriented and relational databases can be im-plemented on top of Dali. Permisrion io copy wiihoui fee all OT pari of this material ir granied provided thai the copies are not made 01 diriribuied for direci cornmenial advantage, the VLDB copyright notice and the title of the publication and ii8 dale appeur, and notice ia given thaf copying ir by pennirrion of the Very Large Data Bare Endowment. To copy otherwire, or to republish, requires a fee and/or special pennirrion from the Endowment