The FIDS Theorems: Tensions between Multinode and Multicore Performance in Transactional Systems

TL;DR

This paper explores the inherent tradeoffs in modern distributed and parallel transactional systems, revealing tensions between fast communication, fault tolerance, and scalability, and proposing solutions when these properties are relaxed.

Contribution

It formalizes the tradeoffs between communication speed, fault tolerance, and scalability in combined distributed and multicore transactional systems, and demonstrates how relaxing certain properties enables system construction.

Findings

Inherent tension exists between fast communication and fault tolerance.

Removing one property allows for scalable parallel distributed systems.

Formalization of key properties guiding system design.

Abstract

Traditionally, distributed and parallel transactional systems have been studied in isolation, as they targeted different applications and experienced different bottlenecks. However, modern high-bandwidth networks have made the study of systems that are both distributed (i.e., employ multiple nodes) and parallel (i.e., employ multiple cores per node) necessary to truly make use of the available hardware. In this paper, we study the performance of these combined systems and show that there are inherent tradeoffs between a system's ability to have fast and robust distributed communication and its ability to scale to multiple cores. More precisely, we formalize the notions of a \emph{fast deciding} path of communication to commit transactions quickly in good executions, and \emph{seamless fault tolerance} that allows systems to remain robust to server failures. We then show that there is an inherent tension between these two natural distributed properties and well-known multicore scalability properties in transactional systems. Finally, we show positive results; it is possible to construct a parallel distributed transactional system if any one of the properties we study is removed.