In this work we present OSARE, an active replication protocol for transactional systems that combines the usage of Optimistic Atomic Broadcast with a speculative concurrency control mechanism in order to overlap transaction processing and replica synchronization. OSARE biases the speculative serialization of transactions towards an order aligned with the optimistic message delivery order. However, due to the lock-free nature of its concurrency control algorithm, at high concurrency levels, namely when the probability of mismatches between optimistic and final deliveries is higher, OSARE explores additional alternative transaction serialization orders in a lightweight and opportunistic fashion. A simulation study we carried out in the context of Software Transactional Memory systems shows that OSARE achieves robust performance also in scenarios characterized by non-minimal likelihood of reorder between optimistic and final deliveries, providing remarkable speed-up with respect to state of the art speculative replication protocols. © 2011 IEEE.
OSARE: Opportunistic speculation in actively REplicated transactional systems / PALMIERI, ROBERTO; QUAGLIA, Francesco; ROMANO, Paolo. - (2011), pp. 59-64. (Intervento presentato al convegno 2011 30th IEEE International Symposium on Reliable Distributed Systems, SRDS 2011 tenutosi a Madrid; Spain nel 4 October 2011 through 7 October 2011) [10.1109/srds.2011.16].
OSARE: Opportunistic speculation in actively REplicated transactional systems
PALMIERI, ROBERTO;QUAGLIA, Francesco;ROMANO, Paolo
2011
Abstract
In this work we present OSARE, an active replication protocol for transactional systems that combines the usage of Optimistic Atomic Broadcast with a speculative concurrency control mechanism in order to overlap transaction processing and replica synchronization. OSARE biases the speculative serialization of transactions towards an order aligned with the optimistic message delivery order. However, due to the lock-free nature of its concurrency control algorithm, at high concurrency levels, namely when the probability of mismatches between optimistic and final deliveries is higher, OSARE explores additional alternative transaction serialization orders in a lightweight and opportunistic fashion. A simulation study we carried out in the context of Software Transactional Memory systems shows that OSARE achieves robust performance also in scenarios characterized by non-minimal likelihood of reorder between optimistic and final deliveries, providing remarkable speed-up with respect to state of the art speculative replication protocols. © 2011 IEEE.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
