DORA: Exploring a Dynamic File Assignment Strategy with Replication

The problem of managing and distributing files to maximize disk performance has been a popular topic of many discussions [1][2][3][4][5]. There are several effective static algorithms that have addressed this issue such as the static round robin (SOR) algorithm. SOR has been proven to produce better response time than other static algorithms such as Greedy, Sort Partition (SP), and Hybrid Partition (HP) [1]. SOR is unique compared to the other static algorithms because it provides considerable performance improvements even if the workload assumption, which says that there is an inverse correlation between file size and its popularity (small files are more popular than large files), does not hold [1]. However, as its name states, it is a static algorithm, and its functionality is limited by the assumption that files and their access patterns do not change over time. In reality, however, this assumption is not accurate for all workloads. We, therefore, propose a new dynamic algorithm called dynamic round robin with replication (DORA). There are two main characteristics of DORA: first, it takes into account the dynamic nature of file or data access patterns to uniquely adapt to changing user demand, and second, it utilizes file replication to further minimize response time and maximize throughput. Moreover, experimental results will show that DORA performs significantly better than another dynamic algorithm, Cool Vanilla (C-V).