TAILIEUCHUNG - Lecture Database system concepts - Chapter 25: Advanced transaction processing
In this chapter, we go beyond the basic transaction processing schemes discussed previously, and cover more advanced transaction-processing concepts, including trans-action-processing monitors, workflow systems, main-memory databases, real-time transaction systems, and handling of long-duration transactions by means of nested transactions, multi-level transactions and weak degrees of consistency. | Chapter 24: Advanced Transaction Processing Transaction-Processing Monitors Transactional Workflows High-Performance Transaction Systems Main memory databases Real-Time Transaction Systems Long-Duration Transactions Transaction management in multidatabase systems Database System Concepts, 5th Ed. ©Silberschatz, Korth and Sudarshan Transaction Processing Monitors TP monitors initially developed as multithreaded servers to support large numbers of terminals from a single process. Provide infrastructure for building and administering complex transaction processing systems with a large number of clients and multiple servers. Provide services such as: Presentation facilities to simplify creating user interfaces Persistent queuing of client requests and server responses Routing of client messages to servers Coordination of two-phase commit when transactions access multiple servers. Some commercial TP monitors: CICS from IBM, Pathway from Tandem, Top End from NCR, and Encina from Transarc Database System Concepts, 5th Ed. ©Silberschatz, Korth and Sudarshan TP Monitor Architectures Database System Concepts, 5th Ed. ©Silberschatz, Korth and Sudarshan TP Monitor Architectures (Cont.) Process per client model - instead of individual login session per terminal, server process communicates with the terminal, handles authentication, and executes actions. Memory requirements are high Multitasking- high CPU overhead for context switching between processes Single process model - all remote terminals connect to a single server process. Used in client-server environments Server process is multi-threaded; low cost for thread switching No protection between applications Not suited for parallel or distributed databases Database System Concepts, 5th Ed. ©Silberschatz, Korth and Sudarshan TP Monitor Architectures (Cont.) Many-server single-router model - multiple .
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