2013 43rd Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN) (2006)
June 25, 2006 to June 28, 2006
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/DSN.2006.33
Evgenia Smirni , College of William and Mary, Williamsburg, VA
Ningfang Mi , College of William and Mary, Williamsburg, VA
Qi Zhang , College of William and Mary, Williamsburg, VA
Erik Riedel , Seagate Research, 1251 Waterfront Place, Pittsburgh, PA
Alma Riska , Seagate Research, 1251 Waterfront Place, Pittsburgh, PA
As most computer systems are expected to remain operational 24 hours a day, 7 days a week, they must complete maintenance work while in operation. This work is in addition to the regular tasks of the system and its purpose is to improve system reliability and availability. Nonetheless, additional work in the system, although labeled as best effort or low priority, still affects the performance of foreground tasks, especially if background/foregroundwork is non-preemptive. In this paper, we propose an analytic model to evaluate the performance trade-offs of the amount of background work that a storage system can sustain. The proposed model results in a quasi-birth-death (QBD) process that is analytically tractable. Detailed experimentation using a variety of workloads shows that under dependent arrivals both foreground and background performance strongly depends on system load. In contrast, if arrivals of foreground jobs are independent, performance sensitivity to load is reduced. The model identifies dependence in the arrivals of foreground jobs as an important characteristic that controls the decision of how much background load the system can accept to maintain high availability and performance gains.
Foreground/background jobs; storage systems; idle periods; Markov Modulated Poisson Process, QBD.
Evgenia Smirni, Ningfang Mi, Qi Zhang, Erik Riedel, Alma Riska, "Evaluating the Performability of Systems with Background Jobs", 2013 43rd Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN), vol. 00, no. , pp. 495-504, 2006, doi:10.1109/DSN.2006.33