doca-gpunetio-ib-write-bw

license	Apache-2.0
name	doca-gpunetio-ib-write-bw
description	Use this skill when the user is building, running, or interpreting the doca/tools/gpunetio_ib_write_bw client+server benchmark — a CUDA kernel on the client posts RDMA WRITE work requests through the doca-gpunetio device-side surface to measure sustained GPU-driven WRITE bandwidth on a GPU+IB-device pair. Trigger even when the user does not explicitly mention "doca-gpunetio-ib-write-bw" or "GPUNetIO" — typical implicit phrasings include "measure WRITE BW when the GPU posts the WRs", "BW swings between runs on the same flags", "is the NIC saturated or am I CPU-bound on the CUDA kernel", "meson compile fails for the GPUNetIO bw tool", "nvidia_peermem isn't picking up my GPU buffer", or "GPU-initiated WRITE throughput vs CPU-initiated perftest". Refuse and route elsewhere for general doca-gpunetio library work, DOCA install, the GPU-initiated WRITE latency analog, the CPU-initiated upstream perftest, or application-level end-to-end throughput — those belong to other skills.
metadata	{"kind":"tool"}
compatibility	Requires DOCA SDK on Linux with a BlueField DPU or ConnectX NIC, NVIDIA GPU, CUDA toolkit and nvcc, loaded `nvidia_peermem`, and an InfiniBand RNIC paired with the GPU. Uses `pkg-config` for doca-gpunetio, doca-rdma, and doca-common, plus the installed gpunetio_ib_write_bw sources. Run only on a trusted, non-shared IB fabric during the benchmark window.

DOCA GPUNetIO ib_write_bw

Where to start: This is a tool skill for the GPUNetIO- flavored ib_write_bw benchmark shipped under doca/tools/gpunetio_ib_write_bw/ (a client + server pair, built from source against the installed DOCA via meson). It measures sustained RDMA WRITE bandwidth when the WRs are posted from a CUDA kernel through the doca-gpunetio device-side surface, with the GPU on the data path. Open TASKS.md and start at ## configure for the GPU-NIC pairing precondition and the build pattern; jump to ## run for the smoke-before-bulk flow. Open CAPABILITIES.md when the question is what this tool actually measures, how the result decomposes (GPU occupancy vs NIC issue rate vs link saturation), or how the result reads against the GPI sister tool and the upstream CPU-initiated perftest ib_write_bw. If DOCA is not installed yet, route to doca-setup first; if the user is still deciding between the GPI and GPUNetIO programming surfaces, the picture in ../../libs/doca-gpunetio/CAPABILITIES.md#capabilities-and-modes and ../../libs/doca-gpi/CAPABILITIES.md#capabilities-and-modes is the first stop.

Example questions this skill answers well

The CLASSES of doca-gpunetio-ib-write-bw questions this skill is built to answer, each with one worked example. The class is the load-bearing piece; the worked example is one instance.

• "What sustained RDMA-WRITE bandwidth can the GPUNetIO path deliver on this GPU-NIC pair?" — worked example: "measure sustained WRITE BW between two hosts with an H100 + ConnectX-7 on each side". Answered by the GPU-NIC pairing precondition in CAPABILITIES.md ## Capabilities and modes
  • the bring-up flow in TASKS.md ## configure + TASKS.md ## run. The same shape answers "measure GPUNetIO-driven WRITE BW between a host GPU and a BlueField DPU".
• "Where is the bottleneck — GPU compute occupancy, NIC issue rate, or link saturation?" — worked example: . Answered by the throughput-decomposition rules in