Reducing Transaction Abort Rates with Prioritized Atomic Multicast Protocols

Priority atomic multicast (i.e., total-order multicast) is a message delivery service that allows an application to prioritize the delivery of certain messages over others, while keeping the regular total order properties. Such a service can be used by applications of different types. As an example, such a prioritybased message delivery service can be used by a replication middleware to reduce the abortion rate of the transactions being applied. In [9] we identified different priorization techniques and studied how to apply them modifying different classes of total order protocols to offer a priority-based total order delivery service. In this report we continue this work presenting an experimental study of these techniques. In this study, we compare three classical total order protocols against their corresponding prioritized versions. To this end we use a test application that broadcasts prioritized messages using these protocols and use some criteria to measure the effect of the priorization. We show that, under certain conditions, the use of prioritized protocols yields lower abort rates respect to the corresponding non-prioritized protocols.