SWHC-strict weak hybrid coherence model for Pthread

DSM(SVM) is a memory model which was proposed at the 1980s'. DSM solved the problem that scalability was contradict with easy programming and merge their merits. The efficiency of DSM is still a problem. The proposed solutions include prefetching and adopting new coherence model, but neither of them is a perfect solution. Prefetch will be less efficient when there are too many false sharing. The weak, relaxed coherence model is quite different from sequential coherence which was assumed by most programmers intuitively, so programming and debugging becomes very difficult. We have proposed Strict Weak Hybrid Coherence (SWHC) model which can eliminate false sharing and provide more temporal and spatial locality, we also provide a scheme to keep sequential coherent. But SWHC model is complicate, a simplified model for Pthread share memory parallel computing model is proposed in the paper.