Adaptive Write Detection in Home-Based Software DSMs

Write detection is essential in multiple-writer protocols to identify writes to shared pages so that these writes can be correctly propagated. Software DSMs that implement multiple-writer protocol normally employ the virtual memory page fault to detect writes to shared pages. It write-protects shared pages at the beginning of an interval to detect writes of the interval. This paper proposes a new write detection scheme in home-based software DSMs. It automatically recognizes single write to a shared page by its home host and assumes the page will continue to be written by the home host in the future until the page is written by remote hosts. During the period the page is assumed to be singly written by its home host, no write detection of this home page is required and page faults caused by home host write detection can be avoided. Evaluation with some well-known DSM benchmarks in a home based software DSM called JIAJIA reveals that the new write detection can reduce page faults dramat..