Flame graphs using :eflame

The example puzzle is the same as the one in the Sudoku solver test, except with
several more cells filled in. Using the original causes :eflame to time out
while creating the final report (see
proger/eflame#13).

Ensure rebar is installed (the original, not rebar3), and run the following:

    $ MIX_ENV=prod mix do clean, deps.get, deps.compile, compile
    $ MIX_ENV=prod iex -S mix run -e "Backtrex.Profiler.eflame; exit(:normal)"
    $ ./deps/eflame/stack_to_flame.sh < stacks.out > flame-prod.svg

Credit goes to http://learningelixir.joekain.com/profiling-elixir-2/ for getting
me started.

lib/backtrex/profiler.ex

@@ -0,0 +1,25 @@
+defmodule Backtrex.Profiler do
+  alias Backtrex.Examples.Sudoku
+
+  def eflame do
+    :eflame.apply(&run_test/0, [])
+  end
+
+  def example_puzzle do
+    {:ok, puzzle} = Sudoku.Puzzle.from_list([
+      [5,   3, :_, :_,  7, :_, :_,  1,  2],
+      [6,   7, :_,  1,  9,  5, :_,  4, :_],
+      [1,   9,  8,  3, :_, :_,  5,  6,  7],
+      [8,  :_,  9, :_,  6, :_,  4, :_,  3],
+      [4,   2, :_,  8, :_,  3,  7, :_,  1],
+      [7,  :_,  3, :_,  2,  4, :_,  5,  6],
+      [:_,  6, :_,  5, :_,  7,  2,  8, :_],
+      [2,  :_, :_,  4,  1,  9,  6, :_,  5],
+      [:_,  4,  5, :_,  8,  6, :_,  7,  9]])
+    puzzle
+  end
+
+  def run_test do
+    {:ok, :solution, _} = example_puzzle() |> Sudoku.Solver.solve
+  end
+end

mix.exs

@@ -14,14 +14,15 @@ defmodule Backtrex.Mixfile do
   end
 
   def application do
-    [extra_applications: [:logger],
+    [extra_applications: [:logger, :eflame],
      applications: [:logger]]   # format expected by Elixir 1.3
   end
 
   defp deps do
     [
       {:credo, "~> 0.5", only: [:dev, :test]},
       {:dialyxir, "~> 0.4", only: [:dev], runtime: false},
+      {:eflame, ~r/.*/, git: "https://github.com/proger/eflame.git", compile: "rebar compile"},
       {:ex_doc, "~> 0.14", only: :dev},
     ]
   end

mix.lock

@@ -2,6 +2,7 @@
   "credo": {:hex, :credo, "0.5.3", "0c405b36e7651245a8ed63c09e2d52c2e2b89b6d02b1570c4d611e0fcbecf4a2", [:mix], [{:bunt, "~> 0.1.6", [hex: :bunt, optional: false]}]},
   "dialyxir": {:hex, :dialyxir, "0.4.3", "a4daeebd0107de10d3bbae2ccb6b8905e69544db1ed5fe9148ad27cd4cb2c0cd", [:mix], []},
   "earmark": {:hex, :earmark, "1.0.3", "89bdbaf2aca8bbb5c97d8b3b55c5dd0cff517ecc78d417e87f1d0982e514557b", [:mix], []},
+  "eflame": {:git, "https://github.com/proger/eflame.git", "ee3a44b950aeb2434460045274809ad506141a83", []},
   "ex_doc": {:hex, :ex_doc, "0.14.5", "c0433c8117e948404d93ca69411dd575ec6be39b47802e81ca8d91017a0cf83c", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, optional: false]}]},
   "inch_ex": {:hex, :inch_ex, "0.5.5", "b63f57e281467bd3456461525fdbc9e158c8edbe603da6e3e4671befde796a3d", [:mix], [{:poison, "~> 1.5 or ~> 2.0 or ~> 3.0", [hex: :poison, optional: false]}]},
   "poison": {:hex, :poison, "3.0.0", "625ebd64d33ae2e65201c2c14d6c85c27cc8b68f2d0dd37828fde9c6920dd131", [:mix], []}}