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Congestion Control for AI Fabrics

Diagnose RoCE congestion using queue growth, ECN feedback and per-priority pause duration. Compare matched traffic patterns before changing routing or flow control.

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RELATED CONCEPTS

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LESSONS THAT TEACH THIS

Fleet and ReliabilitySpecify isolation by resource and validate the end-to-end promise30 min→Fleet and ReliabilityCapstone: accept a cluster with reproducible evidence and recovery tests360 min→

PRACTICE THIS IN REAL QUESTIONS

Networking, Interconnects & StorageWhat is incast, why does it break an RDMA fabric, and what do ECN and priority flow control each do about it?→Networking, Interconnects & StorageWhat is Ultra Ethernet trying to fix, and does it change how you would choose a fabric today?→Networking, Interconnects & StorageInfiniBand or RoCE version 2 for a new GPU training cluster. Make the call and say what would reverse it.→Networking, Interconnects & StorageAfter a switch firmware update, all-reduce bandwidth across the cluster fell 20 percent. Every link is up and no errors are logged. Find it.→Networking, Interconnects & StorageSeveral unrelated jobs slow down at once and nothing is dropping packets. How do you confirm a pause cascade and find where it started?→GPU & Accelerator ArchitectureExplain GPUDirect RDMA. What does it remove from the data path, and when does it change performance?→