US Patent 7240058 Lock mechanism for a distributed data system

A client-server system may include a primary state of session data. Application servers may include client states of the session data and may access the primary state. The session data may include attributes. The distributed store may provide locked access to the primary state to processes executing within the application servers. While one process has locked access, other processes are not allowed to access the primary state. In one embodiment, the distributed store provides locked access to portions of the primary state to threads executing within a process with locked access. While a portion of the primary state is locked for a thread, other threads cannot access the portion. In one embodiment, the distributed store may request the process to release the locked access. The process may release the locked access in response to the request. In one embodiment, the process may release the locked access when no longer needed.