Track object count types as tags

lib/gitlab/metrics/sampler.rb

@@ -53,7 +53,9 @@ module Gitlab
       end
 
       def sample_objects
-        @metrics << Metric.new('object_counts', ObjectSpace.count_objects)
+        ObjectSpace.count_objects.each do |type, count|
+          @metrics << Metric.new('object_counts', { count: count }, type: type)
+        end
       end
 
       def sample_gc

spec/lib/gitlab/metrics/sampler_spec.rb

@@ -71,7 +71,8 @@ describe Gitlab::Metrics::Sampler do
   describe '#sample_objects' do
     it 'adds a metric containing the amount of allocated objects' do
       expect(Gitlab::Metrics::Metric).to receive(:new).
-        with('object_counts', an_instance_of(Hash)).
+        with('object_counts', an_instance_of(Hash), an_instance_of(Hash)).
+        at_least(:once).
         and_call_original
 
       sampler.sample_objects