NVLINK is one of the more interesting features of NVIDIA's new RTX GPU's. In this post I'll take a look at the performance of NVLINK between 2 RTX 2080 GPU's along with a comparison against single GPU I've recently done. The testing will be a simple look at the raw peer-to-peer data transfer performance and a couple of TensorFlow job runs with and without. The following table lists some useful nvlink options which can be specified with nvcc option --nvlink-options. Inhibit all warning messages. 4.2.9.2.2. --preserve-relocs (-preserve-relocs) Preserve resolved relocations in linked executable. 4.2.9.2.3. --verbose (-v).

May 12, 2020 · 3. If you have NVLink connectivity between 2 GPUs, and you place those 2 GPUs into a P2P relationship, and do transfers between them, those transfers will flow over NVLink. It is not possible to force those transfers to flow over PCIe instead. If you want the transfers to flow over PCIe, then you will need to disable the P2P mode between those .... NVIDIA NCCL The NVIDIA Collective Communication Library (NCCL) implements multi-GPU and multi-node communication primitives optimized for NVIDIA GPUs and Networking. NCCL provides routines such as all-gather, all-reduce, broadcast, reduce, reduce-scatter as well as point-to-point send and receive that are optimized to achieve high bandwidth and low latency over PCIe and NVLink high-speed ....