A virtual memory implementation for a real-time environment is presented. The authors considered the special needs of real-time clients and provided a programmable mechanism for clients to control their memory resource needs and constraints. As a design goal they wanted the API to be as simple as possible. They made it look similar to the Unix interface so that client programs could be ported easily from Unix to the target environment. The authors viewed the implementation as risky from the onset and as a result planned on various mechanisms to tune the system. They also planned on extensive performance tools for the same reason. They have seen benefits in the potential flexibility due to this implementation. The authors describe the client interface, implementation details, performance results from the initial implementation, and recent efficiency improvements.>