A novel adaptive home migration protocol in home-based DSM

Home migration is used to tackle the home assignment problem in home-based software distributed shared memory systems. We propose an adaptive home migration protocol to optimize the single-writer pattern which occurs frequently in distributed applications. Our approach is unique in its use of a per-object threshold which is continuously adjusted to facilitate home migration decisions. This adaptive threshold is monotonously decreasing with increased likelihood that a particular object exhibits a lasting single-writer pattern. The threshold is tuned according to the feedback of previous home migration decisions at runtime. We implement this adaptive home migration protocol in a distributed Java virtual machine that supports truly parallel execution of multithreaded Java applications on clusters. The analysis and the experiments show that our home migration protocol demonstrates both the sensitivity to the lasting single-writer pattern and the robustness against the transient single-writer pattern. In the latter case, the protocol inhibits home migration in order to reduce the home redirection overhead.