PCIe Topology & Bandwidth Tuning

PCIe Topology & Bandwidth Tuning

When TLP Header Overhead Eats 30% of Your Effective PCIe Bandwidth

Here's a number that hurts: a PCIe Gen4 x16 link theoretically pushes 31.5 GB/s. But when you actually move data—say, from an NVMe SSD to GPU memory—y...

PCIe Topology & Bandwidth Tuning

When Asymmetric PCIe Links Make Sense for Non-Uniform Workloads

You've got a workload that doesn't play nice with symmetric PCIe trees. Maybe it's a storage array pulling data from NVMe drives on one side while the...

PCIe Topology & Bandwidth Tuning

Why Retimer Placement Matters More Than Repeater Count in Gen 5 Topologies

Gen 5 is ruthless. At 32 GT/s, every millimeter of trace, every via stub, every connector miter steals signal. Many teams chase higher retimer counts,...

PCIe Topology & Bandwidth Tuning

What to Fix First When Switch Topology Bottlenecks Your NVMe RAID Array

Let's be honest: nobody builds an NVMe RAID array to watch it underperform. You picked the drives, the chassis, the controller—maybe even a fancy PCIe...

PCIe Topology & Bandwidth Tuning

When PCIe Lane Bifurcation Creates Hidden Bandwidth Conflicts in Multi-GPU Setups

You drop in four GPUs. The BIOS says they're all at x16. But your training throughput is half what you expected. Chances are, PCIe lane bifurcation is...

PCIe Topology & Bandwidth Tuning

When Root Port Saturation Limits Data Flow in Multi-Device Quantum Simulations

Quantum simula chew through PCIe bandwidth like nothing else. One simula I helped debug was running four GPUs off a lone x16 slot—through a cheap swit...