Khnum - a scalable rapid application deployment system for dynamic hosting infrastructures

Abstract

In a dynamically scalable hosting infrastructure for E-business computing, servers need to be quickly allocated in order to satisfy a sudden demand for increased computing power for a hosted site. Khnum is the applications and data management component of Oceano - a dynamically scalable hosting infrastructure for E-business computing utilities. It is responsible for server reconfiguration and for application deployment. Application deployment involves all services, configuration directives, executables and data of the application. A hosted site may include several applications. Khnum enables Oceano to rapidly deploy multiple applications to tens of servers simultaneously in just a few minutes. It uses AFS as the infrastructure for secure storage, automatically mapping files and directories onto the new servers' local filesystems and multicasting hot AFS cache content to the new servers. To avoid overloading the AFS servers during the deployment process, the hot cache content is multicast to all the new servers, avoiding the boot storming (or "rushing") effect. This, in turn, improves the scalability of the deployment process; experimental results attest to Khnum's scalability in simultaneously deploying applications to tens of servers.