ApacheCon EU 2014

The Compact Muon Solenoid (CMS) users data management service at The Large Hadron Collider (LHC), named AsyncStageOut, manages more than 300k users' files per day of close to 1000 individual users per month with minimal delays, and providing a real time monitoring to users and service operators, while being highly available. The associated data volume represents a new set of challenges in the areas of database scalability and service performance and efficiency.
The service is designed as a thin application relying only on CouchDB as input and data storage. It has progressed from a limited prototype to a highly adaptable service, which manages and monitors the whole CMS user files steps.
In this presentation, Hassen Riahi will provide an overview of the AsyncStageOut model, present the motivations for using CouchDB, describe the deployment model and discuss the results achieved.