Core Systems


Virtual Consensus in Delos

Consensus-based replicated systems are complex, monolithic, and difficult to upgrade once deployed. As a result, deployed systems do not benefit from innovative research, and new consensus protocols rarely reach production. We propose virtualizing consensus by virtualizing the shared log API, allowing services to change consensus protocols without downtime.


FlightTracker: Consistency across Read-Optimized Online Stores at Facebook

This paper introduces FlightTracker, a family of APIs and systems which now manage consistency for online access to Facebook’s graph. FlightTracker implicitly provides RYW and can be explicitly used to provide alternative consistency guarantees for special use cases; it enables flexible communication patterns between caches, which we have found important as the number of datacenters increases; it extends the same consistency guarantees to cross-shard indexes and materialized views, allowing us to transparently optimize queries; and it provides a uniform primitive for clients to obtain desired consistency guarantees across a variety of data stores.