CSR: NeTS: Medium: Collaborative Research: Cloud Support for Latency-Sensitive Web Services

对于web应用程序，即使是几百毫秒的额外延迟也会显著降低用户体验并降低收益。云服务在帮助应用程序提供商减少用户延迟方面处于有利地位，它为来自全球数百个位置的用户提供服务，这些位置的用户拥有丰富多样的互联网连接到用户的网络。然而，由于各种各样的低效率来源，web服务的性能在实践中往往远远达不到基于云的部署所提供的潜力。例如，许多用户从远程服务器得到不正确的服务。即使从附近的服务器提供服务，性能也可能由于迂回路由或拥塞而降低。这些次优结果源于应用程序和云提供商之间用于表达目标和实现结果的有限接口，并且它们的目标通常不匹配。该项目采用多管齐下的跨层方法，使云服务能够优化其托管的web服务提供的性能。首先，研究人员将开发一种新的方法，将客户端引导到附近的服务器，结合现有方法的优点，以克服它们的弱点。本研究的一部分还包括调查如何联合优化客户机到服务器的重定向和后端数据放置，以满足端到端性能目标。其次，该项目将涉及大规模的web传输性能和异常研究，以便为低延迟传输协议的设计提供信息。最后，研究人员将设计一个系统，允许云租户利用云提供商可用的丰富域间路由，以便最好地平衡不同的性能和成本限制。因此，该项目将综合运行高性能web服务的各种相互依赖的方面。研究人员将与流行云服务提供商合作，对工业实践产生变革性影响，并实现现实世界的影响。通过为云提供商开发解决方案来部署他们托管的所有应用程序，该项目将使应用程序提供商受益，而无需他们自己构建和部署这些解决方案。在适用的情况下，研究人员还将在nsf资助的对等网络和CloudLab测试平台上部署他们的系统原型，其他研究人员可以使用它们来构建自己的实验应用程序。研究人员致力于通过公开分享作为该项目的一部分收集的测量数据来帮助其他研究工作。

For web applications, as little as hundreds of milliseconds of additional delay has been found to significantly degrade user experience and lower revenue. Cloud services are well-positioned to help application providers reduce users' latency by serving users from hundreds of locations across the world that have rich and diverse Internet connectivity to users' networks. However, due to various sources of inefficiency, web service performance in practice often falls well short of the potential that cloud-based deployments offer. For example, many users are incorrectly served from distant servers. Even when served from a nearby server, performance can be degraded due to circuitous routing or congestion. These suboptimal outcomes stem from the limited interface between applications and cloud providers to express goals and achieve outcomes, and often a mismatch in their goals.This project pursues a multi-pronged cross-layer approach to enable cloud services to optimize the performance offered by web services they host. First, the researchers will develop a new approach for directing clients to nearby servers, combining the strengths of existing approaches in order to overcome their weaknesses. Part of this research will also include an investigation of how to jointly optimize client-to-server redirection and back-end data placement in order to satisfy end-to-end performance objectives. Second, this project will involve large-scale studies of web transport performance and anomalies in order to inform the design of low-latency transport protocols. Lastly, the researchers will design a system to allow cloud tenants to take advantage of the rich interdomain routing available to cloud providers, in order to best balance diverse performance and cost constraints. Thus, this project will synthesize various inter-dependent aspects of running a high performance web service.The researchers will collaborate with the providers of popular cloud services to have a transformative effect on industrial practice and enable real-world impact. By developing solutions for cloud providers to deploy for all applications they host, this project will benefit application providers without them having to build and deploy these solutions themselves. Where applicable, the researchers will also deploy prototypes of their systems on the NSF-funded PEERING and CloudLab testbeds, which other researchers can use to build their own experimental applications. The researchers are committed to aiding other research efforts by publicly sharing measurements gathered as part of this project.