More optimism about real-time distributed commit processing

In [6], we proposed a new commit protocol, OPT, specially designed for use in distributed firm-deadline real-time database systems. OPT allows transactions to “optimistically” borrow uncommitted prepared data in a controlled manner. This controlled borrowing reduces the data inaccessibility and the priority inversion that is inherent in realtime commit processing. Experimental evaluations showed the new OPT protocol to be highly successful, as compared to the classical distributed commit protocols, in minimizing the number of missed transaction deadlines. In this paper, we extend and improve upon this prior work in the following ways: First, we consider parallel distributed transactions whereas the previous study was restricted to sequential transactions. Second, we evaluate the extent to which OPT’s real-time performance is adversely affected by those cases where its optimism turns out to be misplaced. This is achieved by comparing OPT’s performance with that of Shadow-OPT, ...

• Type: Conference
• Year: 1997
• Where: RTSS
• Authors: Ramesh Gupta, Jayant R. Haritsa, Krithi Ramamritham
• Keywords: Commit Protocols, Control Systems, OPT Allows Transactions, OPT’s Real-time Performance, RTSS 1997