As GPUs have proliferated and become more common in high performance computing (HPC), NVLink provides a significant performance benefit for GPU-to-GPU (peer-to-peer) communication. NVLink is an energy-efficient, high-bandwidth path between GPUs that produces significant speed-ups in application performance and creating high-density, scalable servers for accelerated computing. It offers 5 to 12 times the bandwidth over PCIe and is available with NVIDIA Pascal GPUs (SXM2).

How it works

To see how NVLink technology works, let’s take a look at the Exxact Tensor TXR410-3000R which features the NVLink high-speed interconnect and 8x Tesla P100 Pascal GPUs. NVLink interconnects multiple GPUs (up to eight Tesla P100 in this case). Each GPU has four interconnects that total 80GB/s of bandwidth. Below is an example of two sets of quad P100s directly connected to each other.

nvlink-diagram

This provides up to 160GB/s of GPU bandwidth to peers, load/store access to Peer Memory, full atomics to Peer GPUs, and high speed copy engines for bulk data copy. Connection to CPU is via PCIe, but GPU-CPU interconnect is also available with NVLink port enhanced CPUs.

Applications

NVLink improves application performance by speeding up data movement in multi-GPU configurations. Applications that rely on exchanging data across GPUs can run much faster using NVLink than through the PCIe bus. Below is a list of some applications that can benefit from NVLink:

• Multi-GPU Exchange and sort
• Fast Fourier Transform (FFT)
• AMBER – Molecular Dynamics (PMEMD)
• ANSYS Fluent – Computational Fluid Dynamics
• Lattice Quantum Chromodynamics (LQCD)

Interested in NVLink technology?

If you’re interested in seeing how you can benefit using NVLink technology, speak to one of our experts to help design and build a high-performance system that fits all of your needs. Visit our NVIDIA Tesla Pascal Solutions page for more information on NVLink or contact us directly here.