Move approximate counters to batch counting

changelogs/unreleased/210332-approximate-counters-are-not-working-on-gitlab-com.yml

+---
+title: Use batch counters instead of approximate counters in usage data
+merge_request: 27218
+author:
+type: performance

lib/gitlab/usage_data.rb

@@ -2,7 +2,6 @@
 
 module Gitlab
   class UsageData
-    APPROXIMATE_COUNT_MODELS = [Label, MergeRequest, Note, Todo].freeze
     BATCH_SIZE = 100
 
     class << self
@@ -107,10 +106,12 @@ module Gitlab
             suggestions: count(Suggestion),
             todos: count(Todo),
             uploads: count(Upload),
-            web_hooks: count(WebHook)
+            web_hooks: count(WebHook),
+            labels: count(Label),
+            merge_requests: count(MergeRequest),
+            notes: count(Note)
           }.merge(
             services_usage,
-            approximate_counts,
             usage_counters,
             user_preferences_usage,
             ingress_modsecurity_usage
@@ -251,16 +252,6 @@ module Gitlab
         fallback
       end
 
-      def approximate_counts
-        approx_counts = Gitlab::Database::Count.approximate_counts(APPROXIMATE_COUNT_MODELS)
-
-        APPROXIMATE_COUNT_MODELS.each_with_object({}) do |model, result|
-          key = model.name.underscore.pluralize.to_sym
-
-          result[key] = approx_counts[model] || -1
-        end
-      end
-
       def installation_type
         if Rails.env.production?
           Gitlab::INSTALLATION_TYPE

spec/lib/gitlab/usage_data_spec.rb

@@ -387,29 +387,6 @@ describe Gitlab::UsageData do
           expect(described_class.count(relation, fallback: 15, batch: false)).to eq(15)
         end
       end
-
-      describe '#approximate_counts' do
-        it 'gets approximate counts for selected models', :aggregate_failures do
-          create(:label)
-
-          expect(Gitlab::Database::Count).to receive(:approximate_counts)
-                                               .with(described_class::APPROXIMATE_COUNT_MODELS).once.and_call_original
-
-          counts = described_class.approximate_counts.values
-
-          expect(counts.count).to eq(described_class::APPROXIMATE_COUNT_MODELS.count)
-          expect(counts.any? { |count| count < 0 }).to be_falsey
-        end
-
-        it 'returns default values if counts can not be retrieved', :aggregate_failures do
-          described_class::APPROXIMATE_COUNT_MODELS.map do |model|
-            model.name.underscore.pluralize.to_sym
-          end
-
-          expect(Gitlab::Database::Count).to receive(:approximate_counts).and_return({})
-          expect(described_class.approximate_counts.values.uniq).to eq([-1])
-        end
-      end
     end
   end
 end