Software DSM systems su er from the high communication and coherence-induced overheads that limit performance. This paper introduces our e orts in reducing system overheads of a home-based software DSM called JIAJIA. Three measures, including eliminating false sharing through avoiding unnecessarily invalidating cached pages, reducing virtual memory page faults with a new write detection scheme, and propagating barrier message in a hierarchical way, are taken to reduce the system overhead of JIAJIA. Evaluation with some well-known DSM benchmarks reveals that, though varying with memory reference patterns of different applications, these measures can reduce system overhead of JIAJIA e ectively.