Remove auto vacuum logic, decrease batch size and interval

db/post_migrate/20190214112022_schedule_sync_issuables_state_id.rb

@@ -11,10 +11,12 @@ class ScheduleSyncIssuablesStateId < ActiveRecord::Migration[5.0]
   # issues count: 13587305
   # merge requests count: 18925274
   #
-  # Using 25000 as batch size should take around 26 hours
-  # to migrate both issues and merge requests
-  BATCH_SIZE = 25000
-  DELAY_INTERVAL = 5.minutes.to_i
+  # Using 5000 as batch size and 115 seconds interval will give:
+  # 2718 jobs for issues - taking ~86 hours
+  # 3786 jobs for merge requests - taking ~120 hours
+  #
+  BATCH_SIZE = 5000
+  DELAY_INTERVAL = 120.seconds.to_i
   ISSUES_MIGRATION = 'SyncIssuesStateId'.freeze
   MERGE_REQUESTS_MIGRATION = 'SyncMergeRequestsStateId'.freeze
 
@@ -34,14 +36,14 @@ class ScheduleSyncIssuablesStateId < ActiveRecord::Migration[5.0]
 
   def up
     queue_background_migration_jobs_by_range_at_intervals(
-      Issue.where(state_id: nil),
+      Issue.all,
       ISSUES_MIGRATION,
       DELAY_INTERVAL,
       batch_size: BATCH_SIZE
     )
 
     queue_background_migration_jobs_by_range_at_intervals(
-      MergeRequest.where(state_id: nil),
+      MergeRequest.all,
       MERGE_REQUESTS_MIGRATION,
       DELAY_INTERVAL,
       batch_size: BATCH_SIZE

lib/gitlab/background_migration/reschedulable.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module BackgroundMigration
-    # == Reschedulable helper
-    #
-    # Allows background migrations to be rescheduled if a condition is met,
-    # the condition should be overridden in classes in #should_reschedule? method.
-    #
-    # For example, check DeleteDiffFiles migration which is rescheduled if dead tuple count
-    # on DB is not acceptable.
-    #
-    module Reschedulable
-      extend ActiveSupport::Concern
-
-      # Use this method to perform the background migration and it will be rescheduled
-      # if #should_reschedule? returns true.
-      def reschedule_if_needed(*args, &block)
-        if should_reschedule?
-          BackgroundMigrationWorker.perform_in(wait_time, self.class.name.demodulize, args)
-        else
-          yield
-        end
-      end
-
-      # Override this on base class if you need a different reschedule condition
-      def should_reschedule?
-        raise NotImplementedError, "#{self.class} does not implement #{__method__}"
-      end
-
-      # Override in subclass if a different dead tuple threshold
-      def dead_tuples_threshold
-        @dead_tuples_threshold ||= 50_000
-      end
-
-      # Override in subclass if a different wait time
-      def wait_time
-        @wait_time ||= 5.minutes
-      end
-
-      def execute_statement(sql)
-        ActiveRecord::Base.connection.execute(sql)
-      end
-
-      def wait_for_deadtuple_vacuum?(table_name)
-        return false unless Gitlab::Database.postgresql?
-
-        dead_tuples_count_for(table_name) >= dead_tuples_threshold
-      end
-
-      def dead_tuples_count_for(table_name)
-        dead_tuple =
-          execute_statement("SELECT n_dead_tup FROM pg_stat_all_tables "\
-                            "WHERE relname = '#{table_name}'")[0]
-
-        dead_tuple&.fetch('n_dead_tup', 0).to_i
-      end
-    end
-  end
-end

lib/gitlab/background_migration/sync_issues_state_id.rb

@@ -4,13 +4,10 @@
 module Gitlab
   module BackgroundMigration
     class SyncIssuesStateId
-      include Reschedulable
-
       def perform(start_id, end_id)
         Rails.logger.info("Issues - Populating state_id: #{start_id} - #{end_id}")
 
-        reschedule_if_needed(start_id, end_id) do
-          execute_statement <<~SQL
+        ActiveRecord::Base.connection.execute <<~SQL
           UPDATE issues
           SET state_id =
             CASE state
@@ -22,12 +19,5 @@ module Gitlab
         SQL
       end
     end
-
-      private
-
-      def should_reschedule?
-        wait_for_deadtuple_vacuum?('issues')
-      end
-    end
   end
 end

lib/gitlab/background_migration/sync_merge_requests_state_id.rb

@@ -4,13 +4,10 @@
 module Gitlab
   module BackgroundMigration
     class SyncMergeRequestsStateId
-      include Reschedulable
-
       def perform(start_id, end_id)
         Rails.logger.info("Merge Requests - Populating state_id: #{start_id} - #{end_id}")
 
-        reschedule_if_needed(start_id, end_id) do
-          execute_statement <<~SQL
+        ActiveRecord::Base.connection.execute <<~SQL
           UPDATE merge_requests
           SET state_id =
             CASE state
@@ -24,12 +21,5 @@ module Gitlab
         SQL
       end
     end
-
-      private
-
-      def should_reschedule?
-        wait_for_deadtuple_vacuum?('issues')
-      end
-    end
   end
 end

spec/migrations/schedule_sync_issuables_state_id_spec.rb

@@ -26,33 +26,14 @@ describe ScheduleSyncIssuablesStateId, :migration do
         Timecop.freeze do
           migrate!
 
-          expect(migration).to be_scheduled_delayed_migration(5.minutes, resource_1.id, resource_2.id)
-          expect(migration).to be_scheduled_delayed_migration(10.minutes, resource_3.id, resource_4.id)
+          expect(migration).to be_scheduled_delayed_migration(120.seconds, resource_1.id, resource_2.id)
+          expect(migration).to be_scheduled_delayed_migration(240.seconds, resource_3.id, resource_4.id)
           expect(BackgroundMigrationWorker.jobs.size).to eq(2)
         end
       end
     end
   end
 
-  shared_examples 'rescheduling migrations' do
-    before do
-      Sidekiq::Worker.clear_all
-    end
-
-    it 'reschedules migrations when should wait for dead tuple vacuum' do
-      worker = worker_class.new
-
-      Sidekiq::Testing.fake! do
-        allow(worker).to receive(:wait_for_deadtuple_vacuum?) { true }
-
-        worker.perform(resource_1.id, resource_2.id)
-
-        expect(worker_class.name.demodulize).to be_scheduled_delayed_migration(5.minutes, resource_1.id, resource_2.id)
-        expect(BackgroundMigrationWorker.jobs.size).to eq(1)
-      end
-    end
-  end
-
   describe '#up' do
     context 'issues' do
       it 'migrates state column to integer' do
@@ -76,12 +57,6 @@ describe ScheduleSyncIssuablesStateId, :migration do
         let!(:resource_3) { issues.create!(description: 'third', state: 'closed') }
         let!(:resource_4) { issues.create!(description: 'fourth', state: 'closed') }
       end
-
-      it_behaves_like 'rescheduling migrations' do
-        let(:worker_class) { Gitlab::BackgroundMigration::SyncIssuesStateId }
-        let!(:resource_1) { issues.create!(description: 'first', state: 'opened') }
-        let!(:resource_2) { issues.create!(description: 'second', state: 'closed') }
-      end
     end
 
     context 'merge requests' do
@@ -108,12 +83,6 @@ describe ScheduleSyncIssuablesStateId, :migration do
         let!(:resource_3) { merge_requests.create!(state: 'merged', target_project_id: @project.id, target_branch: 'feature3', source_branch: 'master') }
         let!(:resource_4) { merge_requests.create!(state: 'locked', target_project_id: @project.id, target_branch: 'feature4', source_branch: 'master') }
       end
-
-      it_behaves_like 'rescheduling migrations' do
-        let(:worker_class) { Gitlab::BackgroundMigration::SyncMergeRequestsStateId }
-        let(:resource_1) { merge_requests.create!(state: 'opened', target_project_id: @project.id, target_branch: 'feature1', source_branch: 'master') }
-        let(:resource_2) { merge_requests.create!(state: 'closed', target_project_id: @project.id, target_branch: 'feature2', source_branch: 'master') }
-      end
     end
   end
 end