Make pipeline schedule worker resilientset-real-next-run-at-for-preventing-duplciate-pipeline-creations

Currently, pipeline schedule worker is unstable because it's
sometimes killed by excessive memory consumption.
In order to improve the performance, we add the following fixes:

1. next_run_at is always real_next_run, which means the value
   always takes into account of worker's cron schedule
1. Remove exlusive lock. This is already covered by real_next_run
   change.
1. Use RunPipelineScheduleWorker for avoiding memory killer.
   Memory consumption is spread to the multiple sidekiq worker.

1 files changed, 28 insertions, 0 deletions

diff --git a/spec/services/ci/pipeline_schedule_service_spec.rb b/spec/services/ci/pipeline_schedule_service_spec.rb
new file mode 100644
index 00000000000..f2ac53cb25a
--- /dev/null
+++ b/spec/services/ci/pipeline_schedule_service_spec.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Ci::PipelineScheduleService do
+  let(:project) { create(:project) }
+  let(:user) { create(:user) }
+  let(:service) { described_class.new(project, user) }
+
+  describe '#execute' do
+    subject { service.execute(schedule) }
+
+    let(:schedule) { create(:ci_pipeline_schedule, project: project, owner: user) }
+
+    it 'schedules next run' do
+      expect(schedule).to receive(:schedule_next_run!)
+
+      subject
+    end
+
+    it 'runs RunPipelineScheduleWorker' do
+      expect(RunPipelineScheduleWorker)
+        .to receive(:perform_async).with(schedule.id, schedule.owner.id)
+
+      subject
+    end
+  end
+end