Research And Implementation On Technologies Of Meta-data Load Balancing In Distributed File System

As part of mass storage system, distributed file system provides high- performance, high-availability and high-scalable data access service. There are two types of services in distributed file system, which are meta-data service and file-data service. In order that meta-data service system can extend smoothly, its service management must adjust the workload of meta-data nodes through load balancing.The article's work mainly focuses on following aspects:1. Nodes management strategy based on region autonomy of meta-data service system (MDS system). The strategy divided the system into several regions, each region has a moderate number of nodes. Within the region, it carries out self-organization management. There is a leader node in each region, which contracts the nodes of other region and takes charge of arbitrating in load balancing. Under wide-area distributed environment, dynamic adjustment of region scale and"regional autonomy"strategy guarantee easy-management and high-scalable of meta-data service system.2. Dynamic load balancing strategy based on directory replicating and directory migrating of meta-data service system. The algorithm has two strategies which are directory replicating and directory migrating. Directory replicating strategy has two modes that are"senders driven"and"receivers driven". While appearing hot visit of meta-data at a single node, and"senders driven"will be started to copy this meta-data to another node to disperse visit pressure. And while appearing hot visit of meta-data belonging to other region,"receivers driven"will be started to copy the meta-data from node of other region to disperse visit pressure. Directory migrating strategy is achieved by migrating part workload from overload node to over-light node to balance load of nodes.3. Using the nodes management and load balancing strategy that be mentioned above. Design and implement load balancing sub-system of meta-data service system (Referred to as meta-data load balancing sub-system). The meta-data load balancing sub-system researched is an important component of 863 topic"Development of a new generation management support environment"...