Extended reality (XR) applications require computationally demanding functionalities with low end-to-end latency and high throughput. To enable XR on commodity devices, a number of distributed systems solutions enable offloading of XR workloads on remote servers. However, they make a priori decisions regarding the offloaded functionalities based on assumptions about operating factors, and their benefits are restricted to specific deployment contexts. To realize the benefits of offloading in various distributed environments, we present a distributed stream processing system, FleXR, which is specialized for real-time and interactive workloads and enables flexible distributions of XR functionalities. In building FleXR, we identified and resolved several issues of presenting XR functionalities as distributed pipelines. FleXR provides a framework for flexible distribution of XR pipelines while streamlining development and deployment phases. We evaluate FleXR with three XR use cases in four different distribution scenarios. In the results, the best-case distribution scenario shows up to 50% less end-to-end latency and 3.9x pipeline throughput compared to alternatives.

翻译：扩展现实（XR）应用需要具备高计算需求的功能，同时要求低端到端延迟和高吞吐量。为了在商用设备上实现XR，多种分布式系统解决方案支持将XR工作负载卸载至远程服务器。然而，这些方案基于对运行因素的假设预先确定卸载的功能，其优势受限于特定部署环境。为了在不同分布式环境中实现卸载的收益，我们提出了一个专门用于实时交互式工作负载的分布式流处理系统FleXR，该系统支持XR功能的灵活分布。在构建FleXR的过程中，我们识别并解决了将XR功能呈现为分布式管道的若干问题。FleXR提供了一个框架，可在简化开发与部署流程的同时实现XR管道的灵活分布。我们通过三个XR用例在四种不同分布场景下评估了FleXR。结果表明，与替代方案相比，最优分布场景的端到端延迟降低达50%，管道吞吐量提升至3.9倍。