Active connection management in Internet services

We propose a new connection management architecture for clustered Internet services called active connection management (ACM) to improve the availability, quality of service, and manageability of Internet services. ACM extends the API of load-balancing switches to include application-level primitives. These primitives enable Internet services to manage load-balancing switches dynamically to control how client connections are mapped to physical resources as they enter the cluster. ACM provides several properties ideal for Internet services over static configuration. First, ACM increases availability through automated configuration, rolling reboots, and reduced server failure detection and recovery time. Second, ACM provides better load conditioning by enabling dynamic allocation of front-end resources and enabling more control over graceful degradation. Third, it provides better manageability by automating configuration, reducing human errors and improving scalability. We present a design, implementation, and evaluation of an ACM system, called COMICS (COnnection Manager for Internet-Centric Services), that enables services to actively control how connections are mapped to servers. We believe that ACM primitives should be implemented into future switches and be utilized by application servers to build more robust Internet service platforms.