GitHub

NVTX.jl

NVTX.jl provides Julia bindings to the NVIDIA Tools Extension Library (NVTX) for instrumenting Julia code for use with the Nsight systems profiler.

Installation

NVTX.jl includes the necessary NVTX library for supported platforms, however you will need to install the NVIDIA Nsight Systems to actually run the profiler: it is available for Linux (x86_64, Aarch64, Power) and Windows (x86_64), and the profile viewer is available on Linux, Windows and MacOS.

NVTX.jl can be loaded on any platform, even those without the NVTX library, and so can safely be included as a package dependency.

Instrumenting Julia code

The simplest way to use this package is through the macros NVTX.@mark, NVTX.@range, NVTX.@annotate.

NVTX.@mark "my message"

NVTX.@range "my message" begin
    # code to measure
end

NVTX.@annotate function myfunction(args...)
    # function body
end

Instrumenting Julia internals

Additionally, it is possible to annotate the Julia garbage collector and inference by calling NVTX.enable_gc_hooks() and NVTX.enable_inference_hook(), or setting the JULIA_NVTX_CALLBACKS environment variable to a comma (,) or bar (|) separated list of:

  • gc: instrument the Julia garbage collector
  • alloc: instrument calls to alloc
  • free: instrument calls to free
  • inference: instrument calls to compiler inference.

Running the profiler

To run the Nsight Systems profiler on a script, use

nsys profile julia script.jl

See Nsight Systems User Manual for more information.