Semantically Reliable Broadcast: Sustaining High Throughput in Reliable Distributed
Systems.
J. Pereira, L. Rodrigues and R. Oliveira
This report will be published as a chapter of the following book:
Concurrency in Dependable Computing, Paul Ezhilchelvan and Alexander
Romanovsky (eds.), Chapter 10. 2002 Kluwer Academic Publishers. (to
appear)
Abstract
Replicated services are often required to sustain
high loads of multiple concurrent requests. This requirement is hard
to balance with strong consistency. Typically, to ensure inter-replica
consistency, all replicas should receive all updates. Unfortunately,
in this case, a single slow replica may degrade the performance of the
whole system. This paper proposes a novel reliable broadcast
primitive that uses semantic knowledge to weaken reliable delivery
guarantees while, at the same time, ensuring strong consistency at the
semantic level. By allowing some obsolete messages to be dropped, the
protocol that implements this primitive is able to sustain a higher
throughput than a fully reliable broadcast protocol. The usefulness of
the primitive and the performance of the protocol are illustrated
through a concrete example.
Not available online
Luís Rodrigues