A significant open issue in cloud computing is the real performance of the infrastructure. Few, if any, cloud providers or technologies offer quantitative performance guarantees. Regardless of the potential advantages of the cloud in comparison to enterprise-deployed applications, cloud infrastructures may ultimately fail if deployed applications cannot predictably meet behavioral requirements. In this paper, we present the results of comprehensive performance experiments we conducted on Windows Azure from October 2009 to February 2010. In general, we have observed good performance of the Windows Azure mechanisms, although the average 10 min VM startup time must be accounted for in application design. We also present performance and reliability observations and analysis from our deployment of a large-scale scientific application hosted on Azure, called ModisAzure, that show unusual and sporadic VM execution slowdown of over 4× in some cases and affected up to 16% of task executions at times. In addition to a detailed performance evaluation of Windows Azure, we provide recommendations for potential users of Windows Azure based on these early observations. Although the discussion and analysis is tailored to scientific applications, the results are broadly applicable to the range of existing and future applications running in Windows Azure.

中文翻译：

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Windows Azure性能的早期观察

云计算中一个重要的开放问题是基础架构的实际性能。几乎没有云提供商或技术提供定量的性能保证。无论与企业部署的应用程序相比，云计算有何潜在优势，如果部署的应用程序无法预期地满足行为要求，云基础架构最终可能会失败。在本文中，我们介绍了从2009年10月到2010年2月在Windows Azure上进行的综合性能实验的结果。总体而言，尽管必须考虑平均10分钟的VM启动时间，但Windows Azure机制仍具有良好的性能。在应用程序设计中。我们还将通过部署在Azure上托管的大型科学应用程序的部署，提供性能和可靠性的观察和分析，称为ModisAzure，在某些情况下会显示异常和零星的VM执行速度降低4倍以上，有时会影响高达16％的任务执行。除了对Windows Azure进行详细的性能评估之外，我们还根据这些早期观察为潜在的Windows Azure用户提供建议。尽管讨论和分析是针对科学应用程序而设计的，但结果仍可广泛应用于Windows Azure中运行的现有和将来的应用程序范围。