Tetris：面向可重排无阻塞光子互连的电路调度

中文摘要 AI 辅助

可重构光子互连正成为下一代分布式计算中一种有前景的通信架构。然而，大多数电路调度器都是基于对互连的理想化视图设计的，即将互连视为阻塞式或严格无阻塞式。实际的可扩展设计通常是可重排无阻塞（RNB）的，连接通过内部$2\ imes2$开关网络进行路由。这从根本上改变了调度问题：建立新连接可能迫使现有连接被重新路由，触发多个内部开关的状态变化，并对原本无关的流量施加重配置延迟。我们提出了Tetris，一种面向RNB光子互连的电路调度算法。Tetris基于两个观察。首先，All-to-All需求通常不是双随机的，留下少量端点作为通信瓶颈。其次，重配置延迟可能大到足以改变下一个应调度的连接。Tetris使用剩余通信和重配置工作优先处理瓶颈端点，同时尽可能选择并路由匹配以保持现有连接。匹配确保进展，但连接独立调度，允许完成的连接被替换而无需匹配范围的屏障，并且仅在状态变化的开关处产生延迟。我们的仿真和硬件仿真结果表明，与基于Birkhoff-von Neumann的调度相比，Tetris将All-to-All需求完成时间最多减少$6.6$倍，比Sunflow减少$30$%。更广泛地说，RNB互连在部分重配置的多租户调度和路由方面提出了新问题，我们在论文末尾进行了讨论。

英文摘要

Reconfigurable photonic interconnects are emerging as a promising communication architecture for next-generation distributed computing. Yet, most circuit schedulers are designed around an idealized view of the interconnect as either blocking or strictly non-blocking. Practical scalable designs are often rearrangeably non-blocking (RNB), with connections routed through networks of internal $2\times2$ switches. This changes the scheduling problem fundamentally: establishing a new connection can force existing connections to be rerouted, trigger state changes across multiple internal switches, and impose reconfiguration delay on otherwise unrelated traffic. We present Tetris, a circuit scheduling algorithm for RNB photonic interconnects. Tetris builds on two observations. First, All-to-All demands are often not doubly stochastic, leaving a small number of endpoints as communication bottlenecks. Second, reconfiguration delay can be large enough to change which connection should be scheduled next. Tetris prioritizes bottleneck endpoints using their remaining communication and reconfiguration work, while selecting and routing matchings to preserve ongoing connections whenever possible. Matchings ensure progress, but connections are scheduled independently, allowing completed connections to be replaced without matching-wide barriers and incurring delay only at switches whose states change. Our simulation and hardware-emulation results show that Tetris reduces All-to-All demand completion time by up to $6.6$x over Birkhoff--von Neumann-based scheduling and by $30$% over Sunflow. More broadly, RNB interconnects raise new questions in multi-tenant scheduling and routing for partial reconfiguration, which we discuss at the end of the paper.

发表机构

• Purdue University（普渡大学）

机构由 AI 辅助整理，请以论文原文为准。