Abstract: Method, apparatus and system for data sharing in runtime systems are described. A set of data objects is identified, where each data object in the set of data objects comprises a reference to runtime metadata about the data object in a first runtime system. For each data object in the set of data objects, the reference to the runtime metadata in the data object is replaced with a proxy. The set of data objects is transmitted to a second runtime system. The transmitting of the set of data objects includes replacing the proxy with the reference to the runtime metadata for each of the set of data objects transmitted to the second runtime system. Further, a shared memory is associated with the first runtime system and the second runtime system such that the first and second runtime systems share us information at the shared memory.

Abstract: Methods and apparatus, including computer systems and program products, for sharing objects in runtime systems. A set of objects is identified, each object having a reference to runtime metadata about the object in a first runtime system. The reference to the runtime metadata in each object is replaced with a proxy, and the set of objects is transmitted to a second runtime system, where the proxy in each object is replaced with a reference to runtime metadata about the object in the second runtime system. In some implementations, the runtime metadata can be installed in the second runtime system if it is not already available. The set of objects can include a shared closure of objects, which can be shared between runtime systems (including virtual machines) located on distinct physical machines. Sharing objects between runtime systems on multiple machines can provide isolation between user sessions in a scalable manner.