Python NVTX - Annotate code ranges and events in Python#

NVTX is a cross-platform API for annotating source code to provide contextual
information to developer tools.
The nvtx package provides a Python interface to the NVTX C API.
By default, NVTX API calls do nothing. When a program is launched from a developer tool
(such as NVIDIA Nsight Systems),
NVTX API calls are redirected to the tool’s functions.
Using NVIDIA Nsight Systems,
The NVTX events can be visualized and analyzed in the timeline view.

Installation#

Install using conda (preferred):

conda install -c conda-forge nvtx

Install using pip:

python -m pip install nvtx

Quick Demo#

Here is an example of using nvtx:

# demo.py

import time
import nvtx


def sleep_for(i):
    time.sleep(i)

@nvtx.annotate()
def my_func():
    time.sleep(1)

with nvtx.annotate("for_loop", color="green"):
    for i in range(5):
        sleep_for(i)
        my_func()

Profile the code above using Nsight Systems CLI:

nsys profile python demo.py

This produces a report file (.nsys-rep) which can be viewed in the Nsight Systems GUI:

Overview

API Reference