Providing service quality levels through cpu scheduling

Abstract

In this disclosure, a resource scheduler is described that allows virtual machine instances to earn resource credits during the low activity levels. Virtual machine instances that spend a predominant amount of time operating at low activity levels are able to quickly gain resource credits. Once these virtual machine instances acquire enough resource credits to surpass a threshold level, the resource scheduler can assign a high priority level to the virtual machine instances that provide them with priority access to CPU resources. The next time that the virtual machine instances enter a high activity level, they have a high priority level that allows them to preempt other, lower priority virtual machine instances. Thus, these virtual machine instances are able to process operations and/or respond to user requests with low latency.