Analysis of Spot Prices in Public Cloud Environments

Speaker: Bahman Javadi

Affiliation: University of Wester Sydney

Time: Monday 30/07/2012 from 14:00 to 15:00

Venue: Access Grid UWS. Presented from Parramatta (EB.1.32), accessible from Campbelltown (26.1.50) and Penrith (Y239).

Abstract: The surge in demand for utilizing public Cloud resources has introduced many trade-offs between price, performance and recently reliability. Amazon's Spot Instances (SIs) create a competitive bidding option for the public Cloud users at lower prices without providing reliability on services. It is generally believed that SIs reduce monetary cost to the Cloud users, however it appears from the literature that their characteristics have not been explored and reported. We believe that characterization of SIs is fundamental in the design of stochastic scheduling algorithms and fault tolerant mechanisms in public Cloud environments for spot market. In this paper, we have done a comprehensive analysis of SIs based on one year price history in four data centers of Amazon's EC2. For this purpose, we have analyzed all different types of SIs in terms of spot price and the inter-price time (time between price changes) and determined the time dynamics for spot price in hour-in-day and day-of-week. Moreover, we have proposed a statistical model that fits well these two data series. The results reveal that we are able to model spot price dynamics as well as the inter-price time of each SI by the mixture of Gaussians distribution with three or four components. The proposed model is validated through extensive simulations, which demonstrate that our model exhibits a good degree of accuracy under realistic working conditions.

Biography: Dr Bahman Javadi is a Lecturer in Networking and Cloud Computing at the University of Western Sydney. Before that he appointed as a Research Fellow at the University of Melbourne, Australia. He was a Postdoctoral Fellow at the INRIA Rhone-Alpes, France in 2008-2010. He received his MS and PhD degrees in Computer Engineering from the Amirkabir University of Technology in 2001 and 2007, respectively. He had been a Research Scholar at the School of Engineering and Information Technology, Deakin University, Australia during his PhD course. Dr Javadi is the co-founder of the Failure Trace Archive, which serves as a public repository of failure traces and algorithms for distributed systems. He served as a program committee of many international conferences and workshops and co-guest editor of a special issue of the Journal of Future Generation Computer Systems on Desktop Grids.