This module requires the ezprofiler escript, see...

https://github.com/nhpip/ezprofiler.git

https://hex.pm/packages/ezprofiler

https://hexdocs.pm/ezprofiler/api-reference.html

This module provides the ability to perform code profiling programmatically within an application rather than via the ezprofiler CLI. This maybe useful in environments where shell access maybe limited. Instead the output can be redirected to a logging subsystem for example.

Use of this module still requires the ezprofiler escript, but it will be automatically initialized in the background.

ezprofiler can be downloaded from https://github.com/nhpip/ezprofiler or added to deps in mix.exs along with this package:

defp deps do
  [
    {:ezprofiler, git: "https://github.com/nhpip/ezprofiler.git"},
    {:ezprofiler_deps, git: "https://github.com/nhpip/ezprofiler_deps.git"}
  ]
end

This profiling mechanism supports two modes of operation, synchronous and asynchronous

In synchronous mode the user starts profiling and then calls a blocking call to wait for the results.

In asynchronous mode the results are sent as a message, this will be a handle_info/2 in the case of a GenServer

synchronous-example

Synchronous Example

  EZProfiler.Manager.start_ezprofiler(%EZProfiler.Manager.Configure{ezprofiler_path: :deps})
  ...
  ...
  with :ok <- EZProfiler.Manager.enable_profiling(),
       :ok <- EZProfiler.Manager.wait_for_results(),
       {:ok, filename, results} <- EZProfiler.Manager.get_profiling_results(true)
  do
      {:ok, filename, results}
  else
    rsp ->
      rsp
  end
  ...
  ...
  EZProfiler.Manager.stop_ezprofiler()

asynchronous-example-as-a-genserver

Asynchronous Example as a GenServer

  ## Your handle_cast
  def handle_cast(:start_profiling, state) do
    EZProfiler.Manager.start_ezprofiler(%EZProfiler.Manager.Configure{ezprofiler_path: :deps})
    EZProfiler.Manager.enable_profiling()
    EZProfiler.Manager.wait_for_results_non_block()
    {:noreply, state}
  end

  def handle_info({:ezprofiler, :results_available, filename, results}, state) do
    EZProfiler.Manager.stop_ezprofiler()
    do_something_with_results(filename, results)
    {:noreply, state}
  end

  def handle_info({:ezprofiler, :results_available}, state) do
    {:ok, filename, results} = EZProfiler.Manager.get_profiling_results(true)
    EZProfiler.Manager.stop_ezprofiler()
    {:noreply, state}
  end

  def handle_info({:ezprofiler, :timeout}, state) do
    # Ooops
    EZProfiler.Manager.stop_ezprofiler()
    {:noreply, state}
  end