Recent development in the load balancing single system image (SSI) provides a simple to use, cost effective and high performance environment, which has become increasingly attractive to many users. OpenMosix is one instance of a successful open source SSI cluster. Up date, there is no standard performance measurement metrics suitable for OpenMosix. A standard descriptive performance model benchmark allows developer and user to measure and compare performance of different SSI cluster design. The aim of this part of research is to study the effect of the number of nodes on some performance metrics by considering a particular network configuration and to investigate a framework for performance evaluation and modeling. The performance evaluation and benchmark show that the performance of the cluster is affected by the probabilistic and decentralized approach to disseminate load balancing information. A modification to the dissemination load balancing algorithm shows improved performance.