Modelling Resilience in Cloud-Scale Data Centres
The trend for cloud computing has initiated a race towards Data Centers (DC) of an ever-increasing size. The largest DCs now contain many hundreds of thousands of Virtual Machine (VM) services. Given the finite lifespan of hardware, such large DCs are subject to frequent hardware failure events that can lead to disruption of service. To counter this, multiple redundant copies of task threads may be distributed around a DC to ensure that individual hardware failures do not cause entire jobs to fail. Here, the authors present results demonstrating the resilience of different job scheduling algorithms in a simulated DC with hardware failure. They use a simple model of jobs distributed across a hardware network to demonstrate the relationship between resilience and additional communication costs of different scheduling methods.