The proportion of time a system is in a functioning condition in the watching period. More specifically, the availability during the maintenance is the ratio of system’s available time to the longest maintaining time (i.e., watching period).
Published in Chapter:
Dynamic Maintenance in ChinaGrid Support Platform
Hai Jin (Huazhong University of Science and Technology, China), Li Qi (Huazhong University of Science and Technology, China), Jie Dai (Huazhong University of Science and Technology, China), and Yaqin Luo (Huazhong University of Science and Technology, China)
Copyright: © 2009
|Pages: 9
DOI: 10.4018/978-1-60566-184-1.ch030
Abstract
A grid system is usually composed of thousands of nodes which are broadly distributed in different virtual organizations. Owing to geographical boundaries among these organizations, the system administrators suffer a great pressure to coordinate when grid system experiences a maintaining period. Furthermore, the runtime dynamicity of service state aggravates the complexity of tasks. Consequently, building an efficient and reliable maintaining model becomes an urgent challenge to ensure the correctness and consistency of grid nodes. In our experiment with ChinaGrid, a Dynamic Maintenance mechanism has been adopted in the fundamental grid middleware called ChinaGrid Support Platform. By resolving the above problems with system infrastructure, service dependency and service consistency, the availability of the system can be improved even the scope of maintenance extends to wider region.