Use libring to distribute processes over nodes.

lib/horde/uniform_distribution.ex

@@ -7,27 +7,32 @@ defmodule Horde.UniformDistribution do
 
   def choose_node(identifier, members) do
     members =
-      members
-      |> Enum.filter(fn
-        %{status: :alive} -> true
-        _ -> false
-      end)
-      |> Enum.sort_by(fn %{name: name} -> name end)
+      filter_members(members)
+      |> Map.new(fn member -> {member.name, member} end)
 
     case Enum.count(members) do
       0 ->
         {:error, :no_alive_nodes}
 
       count ->
-        index = hash(term_to_string_identifier(identifier)) |> rem(count)
-        {:ok, Enum.at(members, index)}
+        chosen_member =
+          HashRing.new()
+          |> HashRing.add_nodes(Map.keys(members))
+          |> HashRing.key_to_node(identifier)
+
+        {:ok, Map.get(members, chosen_member)}
     end
   end
 
+  defp filter_members(members) do
+    Enum.filter(members, fn
+      %{status: :alive} -> true
+      _ -> false
+    end)
+  end
+
   defp hash(identifier) when is_integer(identifier), do: identifier
   defp hash(identifier), do: :erlang.phash2(identifier)
 
   def has_quorum?(_members), do: true
-
-  defp term_to_string_identifier(term), do: term |> :erlang.term_to_binary() |> Base.encode16()
 end

mix.exs

@@ -26,6 +26,7 @@ defmodule Horde.MixProject do
   defp deps do
     [
       {:delta_crdt, "~> 0.5.4"},
+      {:libring, "~> 1.4"},
       {:ex_doc, "~> 0.16", only: :dev, runtime: false},
       {:benchee, "> 0.0.1", only: :dev, runtime: false},
       {:stream_data, "~> 0.4", only: :test},

mix.lock

@@ -10,6 +10,7 @@
   "exprintf": {:hex, :exprintf, "0.2.1", "b7e895dfb00520cfb7fc1671303b63b37dc3897c59be7cbf1ae62f766a8a0314", [:mix], [], "hexpm"},
   "exprof": {:hex, :exprof, "0.2.3", "8d4d657d73fc0c9ef1e30b2f9207b26ccbd2aec2baf1ca43f0b6d244c841c9f8", [:mix], [{:exprintf, "~> 0.2", [hex: :exprintf, repo: "hexpm", optional: false]}], "hexpm"},
   "global_flags": {:hex, :global_flags, "1.0.0", "ee6b864979a1fb38d1fbc67838565644baf632212bce864adca21042df036433", [:rebar3], [], "hexpm"},
+  "libring": {:hex, :libring, "1.4.0", "41246ba2f3fbc76b3971f6bce83119dfec1eee17e977a48d8a9cfaaf58c2a8d6", [:mix], [], "hexpm"},
   "local_cluster": {:hex, :local_cluster, "1.0.4", "3cabf9b267cf276752ee6ceccdbe3a05a2125da1b93c5bb74b586ae4539ebd66", [:mix], [{:global_flags, "~> 1.0", [hex: :global_flags, repo: "hexpm", optional: false]}], "hexpm"},
   "makeup": {:hex, :makeup, "0.5.5", "9e08dfc45280c5684d771ad58159f718a7b5788596099bdfb0284597d368a882", [:mix], [{:nimble_parsec, "~> 0.4", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
   "makeup_elixir": {:hex, :makeup_elixir, "0.10.0", "0f09c2ddf352887a956d84f8f7e702111122ca32fbbc84c2f0569b8b65cbf7fa", [:mix], [{:makeup, "~> 0.5.5", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm"},

test/uniform_distribution_test.exs

@@ -8,7 +8,7 @@ defmodule UniformDistributionTest do
                                status <- StreamData.member_of([:alive, :dead, :shutting_down]),
                                name <- binary(),
                                pid <- atom(:alias) do
-        %{node_id: node_id, status: status, pid: pid, name: name}
+        %{node_id: node_id, status: status, pid: pid, name: "A#{name}"}
       end
 
     check all members <- list_of(member),

test/uniform_quorum_distribution_test.exs

@@ -8,7 +8,7 @@ defmodule UniformQuorumDistributionTest do
                                status <- StreamData.member_of([:alive, :dead, :shutting_down]),
                                name <- binary(),
                                pid <- atom(:alias) do
-        %{node_id: node_id, status: status, pid: pid, name: name}
+        %{node_id: node_id, status: status, pid: pid, name: "A#{name}"}
       end
 
     check all members <-