Load balancing is a critical issue for achieving good performance in any parallel and distributed systems. However, this issue is neglected in the research area of software DSMs in the past decade. In this paper, we present and evaluate a dynamic computation scheduling scheme for load balancing of iterative applications in software DSM system. The experiment platform is a home based DSM system named JIAJIA. Preliminary results show that this load balancing scheme is efficient and can be used at any software DSM systems. Furthermore, although simple chunk self scheduling scheme works well for single iteration applications, new affinity-based self scheduling proposed in this paper can improve the system performance about 30\%.