Speculative prefetching of optional locks in distributed systems

We present a family of methods for speeding up distributed locks by exploiting the uneven distribution of both temporal and spatial locality of access behaviour of many applications. In the worst case, some of our methods will not produce higher network latencies than equivalent conventional distributed locking methods. In best case, the total number of messages can be constantly bounded, approximating the impression that no network latencies exist at all. Measurements and simulations based on variants of TPC database benchmarks show that hit rates enabled by speculative prefetching of optional locks appear to be similar to hit rates of conventional data caches, typically in the range from 90% to 99%. Thus overall speedup factors of 10 or more for the average latencies of distributed locks are possible. Compared to purely temporal prefetching, adding exploitation of spatial locality may significantly improve performance, typically by factors of 2 or more. We discuss some implications ...

• Type: Conference
• Year: 2004
• Where: PDCN
• Authors: Thomas Schöbel-Theuer
• Keywords: Distributed Systems, Network Latencies, PDCN 2004, PDCN 2007, Spatial Locality