Adapting to the Unknown With a few Simple Rules: The glideinWMS Experience

Abstract—The High Energy Physics community requires a large amount of compute resources and had to adopt the Grid computing paradigm to satisfy its needs. Scheduling of jobs in the Grid environment is however very challenging, due to the high autonomy enjoyed by the participating resource providers, requiring the user community to constantly adapt to the ever-changing conditions. The CMS experiment addressed this problem by developing the glideinWMS system, which addresses this problem by using an overlay compute pool and a few simple rules for provisioning the needed resources. This approach has been very successful and is now being used by several other communities in the Open Science Grid. This paper provides the description of the glideinWMS system, the algorithms used as well as an analysis of the experience CMS has had using the system. Keywords-layered scheduling; adaptation; glideinWMS. I