In distributed hybrid computing systems, traditional sequential processors are loosely coupled with reconﬁgurable hardware for optimal performance. This loose coupling proves to be a communication challenge; the processor units cannot efﬁciently share a physical memory. This paper proposes a distributed shared memory architecture and a method for effective data migration within that shared memory. Data is moved using a novel garbage collection scheme, the dual semispace collector. The new garbage collector and the distributed memory prove to be an effective means of data migration in distributed hybrid computing systems.