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arXiv · 2609.17057

Budgeted Express-Mesh: Traffic-Aware Link Placement and Deadlock-Free Adaptive Routing

Li Cao·Jingyuan Ma
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Abstract

We present Budgeted Express-Mesh, a topology-routing co-design that adds a small number of traffic-aware express links under a fixed wire budget. An ASPL-based greedy placement is refined by simulation-guided annealing, while packets use committed top-K routes selected from delayed express-link congestion and reservation signals. Across four synthetic workloads, optimized placements consistently improve high-load throughput over Mesh and random placement, and annealing further improves Greedy. The gains persist under delayed quantized congestion information, longer express-link latency, multi-flit packets, and a 16-by-16 heterogeneous workload.

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Li Cao, Jingyuan Ma. 2026-09-16. Budgeted Express-Mesh: Traffic-Aware Link Placement and Deadlock-Free Adaptive Routing. https://arxiv.org/abs/2609.17057

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