CSR: Small: Runtime System Support for Automated Object Recycling

该项目旨在通过自动回收对象来提高大量内存受限的面向对象应用程序的性能。由于面向对象语言固有的低效率以及普遍采用的设计和实现原则，大型面向对象软件通常会遇到系统性能问题。随着面向对象语言被用于通常具有小存储器空间和计算能力的系统（诸如移动的设备）中，这些问题变得越来越关键。在此类系统中，面向对象语言固有的内存效率低下可能会导致严重的性能下降和可扩展性降低。有证据表明，过多的对象创建是内存受限的面向对象应用程序中效率低下的主要原因。 对象回收减少了这种对象创建开销。 回收是通过设计和实现运行时系统支持来实现的，这些支持可以在对象创建时缓存对象，从该高速缓存中检测无法访问的对象，并重用死对象的实例和数据内容。现代生活越来越依赖于内存受限的系统，如智能手机、平板电脑和数据分析工具。该项目为这种内存受限的系统提供了直接的性能优势，从而提高了质量、可用性和用户满意度。此外，这项研究代表了研究界探索新方向的第一步，并可能引发对自动化其他重要（目前手动执行）优化的进一步兴趣。通过OpenJDK和Android社区的开源许可和分发所产生的软件的策略扩展了研究的影响。该项目的教育部分包括创建新的课程材料，招募本科生和代表性不足的群体的学生，以及教育当地程序员如何开发高效的内存限制应用程序。

This project seeks to improve the performance of a wide verity of memory-constrained object-oriented applications by automatically recycling objects. Large-scale, object-oriented software commonly suffers from systemic performance problems, due to inefficiencies inherent in an object-oriented language as well as commonly-adopted design and implementation principles. These problems are becoming increasingly critical as object-oriented languages are used in systems that typically have small memory space and computation power, such as mobile devices. In such systems, memory inefficiencies inherent in an object-oriented language can lead to severe performance degradation and reduced scalability. Evidence suggests that excessive object creation is a major source of inefficiencies in memory-constrained object-oriented applications. Object recycling reduces this object creation overhead. Recycling is achieved by designing and implementing runtime system support that can cache objects upon their creation, detect unreachable objects from the cache, and reuse both instances and data content of dead objects.Modern life relies increasingly on memory-constrained systems such as smartphones, tablets, and data-analytical tools. This project provides an immediate performance benefit for such memory-constrained systems, thereby leading to improved quality, usability, and user satisfaction. In addition, the research represents a first step in a new direction for the research community to explore, and may provoke further interests in automating, other important (currently manually-enforced) optimizations. The impact of the research is extended by a strategy of open-source licensing and distribution of the resulting software through the OpenJDK and Android communities. The educational component of this project includes creation of new course materials, recruitment of undergraduate students and students from under-represented groups, and education of local programmers on how to develop highly-efficient memory-constrained applications.