Computer Science – Distributed – Parallel – and Cluster Computing
Scientific paper
2011-03-31
Computer Science
Distributed, Parallel, and Cluster Computing
15 pages, 2 figures, conference
Scientific paper
The memory consistency model is a fundamental system property characterizing a multiprocessor. The relative merits of strict versus relaxed memory models have been widely debated in terms of their impact on performance, hardware complexity and programmability. This paper adds a new dimension to this discussion: the impact of memory models on software reliability. By allowing some instructions to reorder, weak memory models may expand the window between critical memory operations. This can increase the chance of an undesirable thread-interleaving, thus allowing an otherwise-unlikely concurrency bug to manifest. To explore this phenomenon, we define and study a probabilistic model of shared-memory parallel programs that takes into account such reordering. We use this model to formally derive bounds on the \emph{vulnerability} to concurrency bugs of different memory models. Our results show that for 2 (or a small constant number of) concurrent threads, weaker memory models do indeed have a higher likelihood of allowing bugs. On the other hand, we show that as the number of parallel threads increases, the gap between the different memory models becomes proportionally insignificant. This suggests the counter-intuitive rule that \emph{as the number of parallel threads in the system increases, the importance of using a strict memory model diminishes}; which potentially has major implications on the choice of memory consistency models in future multi-core systems.
Ceze Luis
Effinger-Dean Laura
Jaffe Alexander
Moscibroda Thomas
Strauss Karin
No associations
LandOfFree
The Impact of Memory Models on Software Reliability in Multiprocessors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Impact of Memory Models on Software Reliability in Multiprocessors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Impact of Memory Models on Software Reliability in Multiprocessors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-245257