Performance Isolation in Shared Cloud-based Storage Systems

云计算为企业提供了一个令人振奋的新机会，让他们从构建和管理自己的计算基础设施中解脱出来。只需从云提供商那里购买资源，即可满足计算和在线托管方面的业务需求。然而，由于云提供商无法提供满足客户要求的性能保证，云采用的速度受到了抑制。这个问题的罪魁祸首也是云计算的核心原则：资源共享和超额订阅。云提供商在来自不同业务的多个云计算服务之间共享每台服务器的资源；这提高了资源利用率，降低了托管服务的成本。不幸的是，如果存在严重的资源争用，这种共享可能会导致不一致和不可预测的性能。

Cloud computing represents an exciting new opportunity for businesses to free themselves from building and managing their own computing infrastructure. Business needs in computation and online hosting can be met by simply purchasing resources from Cloud providers. The rate of Cloud adoption, however, has been throttled by the inability of Cloud providers to offer performance guarantees that meet customer requirements. The culprits to this problem are also core tenets of Cloud computing: resource sharing and oversubscription. Cloud providers share each server's resources among multiple Cloud computing services from different businesses; this improves resource utilization and reduces the cost of hosting services. Unfortunately, such sharing can lead to inconsistent and unpredictable performance if there is significant resource contention.