Memory

Direct sharing is standard sharing model in Java (without processes). Direct access to data by different threads. Sharing models:

• Copying---needed if address space not shared (multiple JVMs). Relatively straightforward, but slow and "unappealing".

• Direct sharing---appealing, but complicates process termination and resource reclamation

• Indirect sharing---use proxy objects for sharing. Adds an extra level of indirection to access object, but makes resource reclamation easier. Similar to the idea of a capability in OS for access rights.

Must also handle accounting of allocation/deallocation, perhaps combine with garbage collection.