only include rack.processes if rack suite enabled

README.md

@@ -114,7 +114,7 @@ use Librato::Rack, :config => config
 
 The metrics recorded by `librato-rack` are organized into named metric suites that can be selectively enabled/disabled:
 
-* `rack`: The `rack.request.total`, `rack.request.time`, `rack.request.slow`, and `rack.request.queue.time` metrics
+* `rack`: The `rack.request.total`, `rack.request.time`, `rack.request.slow`, `rack.request.queue.time`, and `rack.processes` metrics
 * `rack_status`: `rack.request.status` metric with `status` tag name and HTTP status code tag value, e.g. `status=200`
 * `rack_method`: `rack.request.method` metric with `method` tag name and HTTP method tag value, e.g. `method=POST`
 

lib/librato/rack/tracker.rb

@@ -125,7 +125,9 @@ def build_flush_queue(collector, preserve=false)
         [collector.counters, collector.aggregate].each do |cache|
           cache.flush_to(queue, preserve: preserve)
         end
-        queue.add 'rack.processes' => { value: 1, tags: tags }
+        if suite_enabled?(:rack)
+          queue.add 'rack.processes' => { value: 1, tags: tags }
+        end
         trace_queued(queue.queued) #if should_log?(:trace)
         queue
       end