Most transactional memories are organized as client-server systems, since they can easily handle concurrent updates by multiple applications. These systems require frequent inter-process communication (IPC) for data fetching, database locking, and transaction control. IPC performance becomes more critical in a transactional memory services where clients and the server exchange data pages, than in relational database systems where only queries and answers are exchanged. Although fast IPC mechanisms have been studied extensively [#!lrpc!#,#!liedtkeSOSP95!#], they have not made their way into mainstream operating systems. Thus, IPC in existing operating systems is slow, and it often becomes the bottleneck in transactional memory implementations.