Rename consumer_utilisation to consumer_capacity

Capacity is 100% when there are online consumers and no messages

deps/rabbit/src/rabbit_amqqueue_process.erl

@@ -110,6 +110,7 @@
          single_active_consumer_tag,
          consumers,
          consumer_utilisation,
+         consumer_capacity,
          memory,
          slave_pids,
          synchronised_slave_pids,
@@ -1118,10 +1119,12 @@ i(messages, State) ->
                                           messages_unacknowledged]]);
 i(consumers, _) ->
     rabbit_queue_consumers:count();
-i(consumer_utilisation, #q{consumers = Consumers}) ->
+i(consumer_utilisation, State) ->
+    i(consumer_capacity, State);
+i(consumer_capacity, #q{consumers = Consumers}) ->
     case rabbit_queue_consumers:count() of
-        0 -> '';
-        _ -> rabbit_queue_consumers:utilisation(Consumers)
+        0 -> 0;
+        _ -> rabbit_queue_consumers:capacity(Consumers)
     end;
 i(memory, _) ->
     {memory, M} = process_info(self(), memory),
@@ -1750,8 +1753,7 @@ handle_pre_hibernate(State = #q{backing_queue = BQ,
       State, #q.stats_timer,
       fun () -> emit_stats(State,
                            [{idle_since,
-                             os:system_time(milli_seconds)},
-                            {consumer_utilisation, ''}])
+                             os:system_time(milli_seconds)}])
                 end),
     State1 = rabbit_event:stop_stats_timer(State#q{backing_queue_state = BQS3},
                                            #q.stats_timer),

deps/rabbit/src/rabbit_fifo.erl

@@ -759,7 +759,7 @@ which_module(1) -> ?MODULE.
 
 -record(aux_gc, {last_raft_idx = 0 :: ra:index()}).
 -record(aux, {name :: atom(),
-              utilisation :: term(),
+              capacity :: term(),
               gc = #aux_gc{} :: #aux_gc{}}).
 
 init_aux(Name) when is_atom(Name) ->
@@ -769,7 +769,7 @@ init_aux(Name) when is_atom(Name) ->
                                       {write_concurrency, true}]),
     Now = erlang:monotonic_time(micro_seconds),
     #aux{name = Name,
-         utilisation = {inactive, Now, 1, 1.0}}.
+         capacity = {inactive, Now, 1, 1.0}}.
 
 handle_aux(leader, _, garbage_collection, State, Log, _MacState) ->
     ra_log_wal:force_roll_over(ra_log_wal),
@@ -779,15 +779,15 @@ handle_aux(follower, _, garbage_collection, State, Log, MacState) ->
     {no_reply, force_eval_gc(Log, MacState, State), Log};
 handle_aux(_RaState, cast, eval, Aux0, Log, _MacState) ->
     {no_reply, Aux0, Log};
-handle_aux(_RaState, cast, Cmd, #aux{utilisation = Use0} = Aux0,
+handle_aux(_RaState, cast, Cmd, #aux{capacity = Use0} = Aux0,
            Log, _MacState)
   when Cmd == active orelse Cmd == inactive ->
-    {no_reply, Aux0#aux{utilisation = update_use(Use0, Cmd)}, Log};
+    {no_reply, Aux0#aux{capacity = update_use(Use0, Cmd)}, Log};
 handle_aux(_RaState, cast, tick, #aux{name = Name,
-                                      utilisation = Use0} = State0,
+                                      capacity = Use0} = State0,
            Log, MacState) ->
     true = ets:insert(rabbit_fifo_usage,
-                      {Name, utilisation(Use0)}),
+                      {Name, capacity(Use0)}),
     Aux = eval_gc(Log, MacState, State0),
     {no_reply, Aux, Log};
 handle_aux(_RaState, {call, _From}, {peek, Pos}, Aux0,
@@ -991,9 +991,11 @@ update_use({inactive, Since, Active, Avg},   active) ->
     Now = erlang:monotonic_time(micro_seconds),
     {active, Now, use_avg(Active, Now - Since, Avg)}.
 
-utilisation({active, Since, Avg}) ->
+capacity({active, Since, Avg}) ->
     use_avg(erlang:monotonic_time(micro_seconds) - Since, 0, Avg);
-utilisation({inactive, Since, Active, Avg}) ->
+capacity({inactive, _, 1, 1.0}) ->
+    1.0;
+capacity({inactive, Since, Active, Avg}) ->
     use_avg(Active, erlang:monotonic_time(micro_seconds) - Since, Avg).
 
 use_avg(0, 0, Avg) ->

deps/rabbit/src/rabbit_queue_consumers.erl

@@ -12,7 +12,7 @@
          send_drained/0, deliver/5, record_ack/3, subtract_acks/3,
          possibly_unblock/3,
          resume_fun/0, notify_sent_fun/1, activate_limit_fun/0,
-         credit/6, utilisation/1, is_same/3, get_consumer/1, get/3,
+         credit/6, utilisation/1, capacity/1, is_same/3, get_consumer/1, get/3,
          consumer_tag/1, get_infos/1]).
 
 %%----------------------------------------------------------------------------
@@ -409,10 +409,13 @@ drain_mode(true)  -> drain;
 drain_mode(false) -> manual.
 
 -spec utilisation(state()) -> ratio().
+utilisation(State) ->
+    capacity(State).
 
-utilisation(#state{use = {active, Since, Avg}}) ->
+-spec capacity(state()) -> ratio().
+capacity(#state{use = {active, Since, Avg}}) ->
     use_avg(erlang:monotonic_time(micro_seconds) - Since, 0, Avg);
-utilisation(#state{use = {inactive, Since, Active, Avg}}) ->
+capacity(#state{use = {inactive, Since, Active, Avg}}) ->
     use_avg(Active, erlang:monotonic_time(micro_seconds) - Since, Avg).
 
 is_same(ChPid, ConsumerTag, {ChPid, #consumer{tag = ConsumerTag}}) ->

deps/rabbit/src/rabbit_quorum_queue.erl

@@ -383,6 +383,7 @@ handle_tick(QName,
                                  _ -> rabbit_fifo:usage(Name)
                              end,
                       Infos = [{consumers, C},
+                               {consumer_capacity, Util},
                                {consumer_utilisation, Util},
                                {message_bytes_ready, MsgBytesReady},
                                {message_bytes_unacknowledged, MsgBytesUnack},

deps/rabbitmq_management/priv/www/js/global.js

@@ -71,7 +71,7 @@ var ALL_COLUMNS =
                    ['features_no_policy',   'Features (no policy)',   false],
                    ['policy',               'Policy',                 false],
                    ['consumers',            'Consumer count',         false],
-                   ['consumer_utilisation', 'Consumer utilisation',   false],
+                   ['consumer_capacity',    'Consumer capacity',      false],
                    ['state',                'State',                  true]],
       'Messages': [['msgs-ready',      'Ready',          true],
                    ['msgs-unacked',    'Unacknowledged', true],
@@ -251,7 +251,7 @@ var HELP = {
     'queue-process-memory':
       'Total memory used by this queue process. This does not include in-memory message bodies (which may be shared between queues and will appear in the global "binaries" memory) but does include everything else.',
 
-    'queue-consumer-utilisation':
+    'queue-consumer-capacity':
       'Fraction of the time that the queue is able to immediately deliver messages to consumers. If this number is less than 100% you may be able to deliver messages faster if: \
         <ul> \
           <li>There were more consumers or</li> \

deps/rabbitmq_management/priv/www/js/tmpl/queue.ejs

@@ -133,8 +133,8 @@
         <td><%= fmt_string(queue.consumers) %></td>
       </tr>
       <tr>
-        <th>Consumer utilisation <span class="help" id="queue-consumer-utilisation"></th>
-        <td><%= fmt_percent(queue.consumer_utilisation) %></td>
+        <th>Consumer capacity <span class="help" id="queue-consumer-capacity"></th>
+        <td><%= fmt_percent(queue.consumer_capacity) %></td>
       </tr>
       <% if (is_quorum(queue) || is_stream(queue)) { %>
       <tr>

deps/rabbitmq_management/priv/www/js/tmpl/queues.ejs

@@ -45,8 +45,8 @@
 <% if (show_column('queues', 'consumers')) { %>
     <th><%= fmt_sort('Consumers',    'consumers') %></th>
 <% } %>
-<% if (show_column('queues', 'consumer_utilisation')) { %>
-    <th><%= fmt_sort('Consumer utilisation', 'consumer_utilisation') %></th>
+<% if (show_column('queues', 'consumer_capacity')) { %>
+    <th><%= fmt_sort('Consumer capacity', 'consumer_capacity') %></th>
 <% } %>
 <% if (show_column('queues', 'state')) { %>
     <th><%= fmt_sort('State',        'state') %></th>
@@ -157,8 +157,8 @@
 <% if (show_column('queues', 'consumers')) { %>
    <td class="c"><%= fmt_string(queue.consumers) %></td>
 <% } %>
-<% if (show_column('queues', 'consumer_utilisation')) { %>
-   <td class="c"><%= fmt_percent(queue.consumer_utilisation) %></td>
+<% if (show_column('queues', 'consumer_capacity')) { %>
+   <td class="c"><%= fmt_percent(queue.consumer_capacity) %></td>
 <% } %>
 <% if (show_column('queues', 'state')) { %>
    <td class="c"><%= fmt_object_state(queue) %></td>

deps/rabbitmq_management/test/rabbit_mgmt_http_SUITE.erl

@@ -2462,7 +2462,8 @@ format_output_test(Config) ->
     http_put(Config, "/queues/%2F/test0", QArgs, {group, '2xx'}),
     timer:sleep(2000),
     assert_list([#{name => <<"test0">>,
-                   consumer_utilisation => null,
+                   consumer_capacity => 0,
+                   consumer_utilisation => 0,
                    exclusive_consumer_tag => null,
                    recoverable_slaves => null}], http_get(Config, "/queues", ?OK)),
     http_delete(Config, "/queues/%2F/test0", {group, '2xx'}),