Dynamo

TLDR

Amazon’s massive e‑commerce platform, spanning tens of thousands of servers across multiple data centers, faces constant component failures, making reliable persistent state management essential for maintaining high availability and customer trust. This work introduces Dynamo, a highly available key‑value store designed to keep Amazon’s core services running continuously. Dynamo achieves availability by tolerating consistency violations during failures, employing extensive object versioning and application‑assisted conflict resolution to give developers a flexible interface.

Abstract

Reliability at massive scale is one of the biggest challenges we face at Amazon.com, one of the largest e-commerce operations in the world; even the slightest outage has significant financial consequences and impacts customer trust. The Amazon.com platform, which provides services for many web sites worldwide, is implemented on top of an infrastructure of tens of thousands of servers and network components located in many datacenters around the world. At this scale, small and large components fail continuously and the way persistent state is managed in the face of these failures drives the reliability and scalability of the software systems. This paper presents the design and implementation of Dynamo, a highly available key-value storage system that some of Amazon's core services use to provide an "always-on" experience. To achieve this level of availability, Dynamo sacrifices consistency under certain failure scenarios. It makes extensive use of object versioning and application-assisted conflict resolution in a manner that provides a novel interface for developers to use.