Grid on Cloud

Recently, dramatic developments have taken place in cloud computing, requiring IT specialists to acquire new cloud skills. Accordingly, universities will need to change their curriculums and educational environments in order to teach advanced information and communication technology to students. Educational organizations such as universities need to provide an educational cloud for use by students. We are constructing a private educational cloud based on the Ubuntu Enterprise Cloud. The most important feature of our cloud is super-saturation, which is defined as allocating more logical resources than the available physical resources. A supersaturated cloud can execute more than 10 times the number of instances than a conventional cloud. In order to maximize the performance of a supersaturated cloud, tasks must continuously be provided to the cloud. However, the demand on grids has been reduced because of energy saving. Thus, the grid and cloud are complementary technologies in that the cloud consumes tasks produced by the grid. In this paper, we propose a method for constructing a Grid on Cloud to solve this issue. We compare two methods, the single large instance strategy (SLIS) and multiple small instance strategy. We conclude that the SLIS based instance grid method is the best if the system load is shared by all instances.