Doca Bench Extension Agent Skill

DOCA Bench Extension

Where to start: This is a tool skill for the **extension /

plug-in framework** that augments

doca-bench — NOT a workload-shape

skill on its own. Open TASKS.md and start at

## configure to commit to the three-axis

decision (workload class is genuinely outside doca-bench's

built-in modes × extension API surface fits × parent-tool

co-load is acceptable), then ## build for

how a custom extension is compiled and laid out, then

## run for how doca-bench discovers and

invokes the extension, then ## test for the

smoke-before-bulk loop the agent applies to every new

extension. Open CAPABILITIES.md when the

question is *what an extension can do that built-in

doca-bench modes cannot*, *what the extension API surface

looks like in broad strokes (the DOCA_EXPERIMENTAL C entry

points the shipped reference exposes)*, *how the

build / registration / discovery flow works*, or *how the

extension's lifetime is bounded by the parent doca-bench

invocation*. If doca-bench itself is the question, route to

doca-bench. If the question is

"which built-in doca-bench mode do I pick?", that is also

doca-bench — extensions are the

*exit ramp* for workloads built-in modes do not cover.

Example questions this skill answers well

• *"My workload class is <X> — does doca-bench measure it

natively, or do I need an extension?"* — the

extension-vs-built-in decision question. The agent walks

the user back to doca-bench's

built-in mode inventory FIRST and only routes to the

extension framework when no built-in mode applies.

• *"I want to benchmark a CUDA / GPU-side workload that

drives DOCA GPUNetIO RX and TX queues. Where do I start?

Is there a reference extension I can copy?"* — the agent

surfaces the shipped doca_bench_cuda extension under

/opt/mellanox/doca/tools/bench_extension/doca_bench_cuda/ as the

reference exemplar and walks the operator through its

API surface and build shape.

• *"How does doca-bench actually discover and load my

custom extension at runtime? Is it a versioned shared

library? What does my entry-point need to look like?"* —

the build / registration / discovery flow question. The

agent walks the Meson-built shared library shape, the

versioning, and the parent-tool's runtime discovery path

(which the agent does NOT invent from memory — the

shipped extension's meson.build and the public DOCA Bench

documentation on docs.nvidia.com are the source of

truth).

• *"The API headers I have are marked DOCA_EXPERIMENTAL.

What does that mean for my extension's stability across

DOCA releases? Am I going to have to rebuild it every

release?"* — the experimental-surface and version

compatibility question.

• *"Once I build my extension, what is the cheapest possible

smoke I can run before pointing my real workload at it?

How do I know doca-bench actually loaded it, called

into it, and that the call returned the data the parent

tool expected?"* — the smoke-before-bulk question.

• *"My custom extension builds, but doca-bench says it

cannot find / load / call it. Where do I look first?"* —

the layered-debug question that distinguishes

build-failures, load-failures, registration-mismatches,

and runtime-call-failures.

Audience

Experienced AI agents and platform / performance engineers

who already use doca-bench for

the built-in workload modes and now have a workload class

that the built-in modes do not cover. Readers are expected

to be comfortable with native build systems (Meson, in this

codebase), shared-library packaging on Linux, and the

DOCA_EXPERIMENTAL API stability contract. If the user

asks about GPU-side benchmarking via the shipped

doca_bench_cuda reference extension, the reader is also

expected to be familiar with DOCA GPUNetIO and CUDA toolchain

basics — those domains live in their own skills, not here.

This skill is NOT for:

• operators who can express their workload with one of

doca-bench's built-in modes — that is

doca-bench;

• operators who want to benchmark a different DOCA primitive

(Flow, Comch, RMAX) via that primitive's own

measurement tool — route to that tool;

• contributors authoring or modifying the in-tree extensions

themselves (this skill is for external operators consuming

the framework, not for internal DOCA contributors).

Language scope

A doca-bench extension surfaces as:

• A versioned shared library on Linux (.so with

soversion matching the DOCA release), built via the

doca-bench-extension Meson rules in the shipped

/opt/mellanox/doca/tools/bench_extension/meson.build and the

per-extension subdirectory (the reference exemplar is

doca_bench_cuda/).

• A small set of **DOCA_EXPERIMENTAL-marked C entry

points** that the parent doca-bench invokes — i.e. the

API surface declared in the extension's header file.

The shipped doca_bench_cuda/doca_bench_cuda.h is the

reference for what that surface shape looks like in

practice (*_init, *_device_query,

*_device_synchronize, and per-workload kernel-start

entry points such as *_start_nop_kernel,

*_start_eth_recv_kernel, *_start_eth_send_kernel,

*_start_eth_bidir_kernel).

• A set of per-workload settings structs that the

parent passes through (e.g. the reference exemplar's

doca_bench_cuda_kernel_settings,

doca_bench_cuda_eth_rx_kernel_settings,

doca_bench_cuda_eth_tx_kernel_settings,

doca_bench_cuda_eth_bidir_kernel_settings carry block

counts, threads-per-block, RX / TX queues, buffer

address / mkey / size, a stop flag, and a stats

pointer).

The skill itself is Markdown. The user's extension source

is whatever language the workload requires (C / C++ / CUDA

in the reference case). The agent does NOT prescribe a

language beyond what the shipped reference demonstrates.

When to load this skill

Load doca-bench-extension when ANY of the following is

true:

• the user explicitly mentions doca-bench-extension, the

doca_bench_cuda reference extension, the

doca_bench_cuda_impl shared library, or any of the

DOCA_EXPERIMENTAL extension entry points;

• the user has confirmed (via

doca-bench TASKS.md ## configure)

that none of doca-bench's built-in workload modes

measures the class they want, and an extension is the

exit ramp;

• the user wants to copy / extend the shipped

doca_bench_cuda reference into a custom GPU-side

workload extension;

• the user is debugging why doca-bench cannot find / load

/ call a custom extension they built.

Co-load this skill with:

• doca-bench (the parent tool —

ALWAYS co-loaded; extensions only have value as

plug-ins into doca-bench);

• doca-version (the

DOCA_EXPERIMENTAL surface is versioned with DOCA; the

extension's soversion is the DOCA soversion; the

four-way version match applies);

• doca-gpunetio when

the extension is GPU-side and uses GPUNetIO RX / TX

queues like the reference exemplar (route the GPUNetIO

semantics there, not here);

• doca-debug and

doca-setup for the

env-side debug ladder (driver, firmware, CUDA toolkit,

dynamic linker).

Do NOT load this skill when the user's workload fits a

doca-bench built-in mode — extensions add cost (build

toolchain, version churn, the experimental-surface

contract); the built-in modes are always the first answer to

try.

What this skill provides

Three companion files in this directory, each owning a

different question shape:

• SKILL.md — this file. Audience, scope,

loading order, related skills. Routes everything else.

• CAPABILITIES.md — *what an extension

can do that the built-in modes cannot*, *what the API

surface looks like in broad strokes*, *how the

build / registration / discovery flow works*, *what

versions it ships in (including the

DOCA_EXPERIMENTAL-stability overlay on top of

doca-version)*, *the layered error taxonomy*,

observability, and the safety policy overlay.

• TASKS.md — the procedural verbs

(configure, build, run, test, debug, etc.) plus

a doca-bench-extension-specific command appendix and

the agent-side use workflow that consumes the captured

extension run.

The combined skill teaches an AI agent to drive the

*extension-author-and-wire-in class* of doca-bench

questions: confirm an extension is needed at all; locate

the shipped reference exemplar

(/opt/mellanox/doca/tools/bench_extension/doca_bench_cuda/); copy

its build + API surface shape; build a versioned shared

library that matches the DOCA release; smoke that the

parent doca-bench actually loads it; diagnose layered

failures when it does not.

What this skill deliberately does not ship

• Inventory of doca-bench's built-in workload modes.

That belongs to doca-bench.

This skill is the exit ramp for what the built-in modes

do not cover; it does not duplicate the parent's mode

inventory.

• **Invented DOCA_EXPERIMENTAL entry-point names beyond

what the shipped reference declares.** The shipped

doca_bench_cuda/doca_bench_cuda.h on the user's

install is the reference for what the surface shape

looks like; the agent does not assert other extensions

exist with specific signatures.

• A canonical "right" extension layout. The shipped

doca_bench_cuda reference IS the canonical layout;

rewriting it here would drift from the source of truth.

The agent points the operator at the shipped tree and

walks the operator through *adapting* it.

• **A documented runtime discovery mechanism the agent

invents.** The exact mechanism doca-bench uses to

locate and load extensions (search path, naming

convention, registration call) lives in the public DOCA

Bench documentation on docs.nvidia.com and the

installed doca-bench binary. The agent points the

operator there rather than asserting a mechanism from

memory.

• DOCA GPUNetIO programming details. When the

extension is GPU-side (as the reference exemplar is),

the GPUNetIO RX / TX queue semantics live in

doca-gpunetio;

this skill cross-links rather than duplicates.

• CUDA toolchain installation guidance. Route to the

public NVIDIA CUDA Toolkit documentation on

docs.nvidia.com; this skill does not duplicate it.

• **Library-internal doca-bench invocation details

unrelated to extensions.** The parent's CLI flags,

pipeline shapes, and built-in workload classes belong

to doca-bench.

Loading order

When a doca-bench-extension question arrives:

• Confirm DOCA is installed AND doca-bench is reachable

on the user's install — if not, route to

doca-setup;

• **Confirm none of doca-bench's built-in modes covers

the workload class** — if any of them does, route back

to doca-bench TASKS.md ## configure

and stop. Extensions are the exit ramp, not the first

answer;

• Read CAPABILITIES.md to commit to

the three-axis decision and walk the reference

exemplar's API surface shape;

• Read TASKS.md and walk

## configure → ## build → ## run → ## test → ## debug

in that order; do NOT start with ## run without the

build precondition step.

Related skills

Cross-link conventions follow the bundle's relative path

contract from tools/<X>/:

• doca-bench — the parent tool.

ALWAYS co-loaded. Extensions are plug-ins into

doca-bench; they do not replace it, they do not have a

standalone CLI, they do not measure anything without the

parent invoking them. Every question on this skill

presupposes the parent.

• doca-version — the

DOCA_EXPERIMENTAL surface is versioned with DOCA; the

extension's soversion matches the DOCA release per

the shipped meson.build. The four-way version match

applies; rebuilding the extension across DOCA upgrades

is the rule, not the exception.

• doca-gpunetio —

when the extension is GPU-side and uses GPUNetIO RX /

TX queues like the reference doca_bench_cuda. Route

the GPUNetIO semantics there.

• doca-setup — DOCA install

posture (does doca-bench exist? does the

doca_bench_cuda_impl reference library exist? is the

CUDA toolchain installed when needed?).

• doca-debug — the

cross-cutting debug ladder for env-side issues (dynamic

linker, library search path, CUDA driver / toolkit,

firmware).

• doca-public-knowledge-map

— routing to the public DOCA Bench / DOCA GPUNetIO pages

on docs.nvidia.com and the release notes for the

documented extension lifecycle / discovery mechanism.

• doca-structured-tools-contract

— the agent's detect → prefer → fall back → report

contract for the structured helpers

(doca-env --json, doca-capability-snapshot,

version-matrix.json) the build / load preconditions

rely on.

• doca-hardware-safety

— the canonical hardware-safety meta-policy that

CAPABILITIES.md ## Safety policy

overlays. Extensions are external code loaded into

doca-bench; the safety implications of loading

experimental code into a benchmark that touches the

dataplane / device are real.

This skill assumes the user has built shared libraries on

Linux before and knows what a Meson build is. Background

material on those topics belongs in the toolchain docs, not

in this skill.