Coflow has emerged as a fundamental application-layer abstraction in distributed systems, representing communication dependencies and enabling collaborative management of related flows to enhance job completion efficiency. To meet the increasing bandwidth demands of modern data center networks (DCNs), optical circuit switches are widely deployed due to their high capacity and energy efficiency. Simultaneously, DCN deployments are evolving towards heterogeneous parallel architectures, where multiple independent optical circuit switching (OCS) cores operate concurrently to facilitate bandwidth expansion and incremental upgrades. However, existing research on coflow scheduling in multi-core switching fabrics primarily focuses on electrical packet switching (EPS) networks, with a few known results on OCS networks without or with a poor performance guarantee. This paper studies the coflow scheduling problem in multi-core OCS networks under the not-all-stop (i.e., asynchronous) reconfiguration model, focusing on two major challenges of overcoming cross-core coupling for inter-core traffic allocation and satisfying the constraints of port exclusivity and reconfiguration overhead for intra-core circuit scheduling. To minimize total weighted coflow completion time (CCT), we propose an efficient algorithm by integrating linear programming-guided (LP-guided) global coflow ordering, inter-core flow allocation and intra-core circuit scheduling that achieves approximation ratios of 8K and 8K+1 for zero and arbitrary release times of coflows, respectively, where K is the number of OCS cores. This framework is also applicable to H-core EPS networks, providing approximation guarantees of 4H and 4H+1 for zero-time and arbitrary-time release, respectively.

翻译：协同流（Coflow）已成为分布式系统中一种基础的应用层抽象，它表征通信依赖关系并支持相关流的协同管理，从而提升作业完成效率。为满足现代数据中心网络不断增长的带宽需求，光电路交换器因其高容量与高能效特性被广泛部署。与此同时，数据中心网络部署正朝着异构并行架构演进，多个独立的光电路交换核心并行运行，以支持带宽扩展与增量升级。然而，现有关于多核交换架构中协同流调度的研究主要集中于电分组交换网络，而针对光电路交换网络的研究结果极少，且缺乏性能保障。本文研究多核光电路交换网络在非全停（即异步）重配置模型下的协同流调度问题，聚焦于克服跨核耦合的核间流量分配以及满足端口排他性与重配置开销约束的核内电路调度这两大挑战。为最小化加权协同流完成时间，我们提出一种高效算法，通过整合线性规划引导的全局协同流排序、核间流量分配与核内电路调度，在协同流零释放时间与任意释放时间下分别实现了8K和8K+1的近似比，其中K为光电路交换核心数。该框架同样适用于H核电分组交换网络，在零释放时间与任意释放时间下分别提供4H和4H+1的近似保证。