Add example benchmark for job throughput

.rubocop.yml

@@ -20,6 +20,7 @@ AllCops:
     - pkg/**/*
     - spec/test_app/**/*
     - vendor/**/*
+    - scripts/**/*
   NewCops: enable
 
 Layout/EmptyLineAfterMagicComment:

Gemfile.lock

@@ -73,6 +73,9 @@ GEM
     activerecord-jdbcpostgresql-adapter (61.0-java)
       activerecord-jdbc-adapter (= 61.0)
       jdbc-postgres (>= 9.4, < 43)
+    activerecord-explain-analyze (0.1.0)
+      activerecord (>= 4)
+      pg
     activestorage (6.1.3.2)
       actionpack (= 6.1.3.2)
       activejob (= 6.1.3.2)
@@ -107,6 +110,7 @@ GEM
       async (~> 1.14)
     async-pool (0.3.6)
       async (~> 1.25)
+    benchmark-ips (2.8.4)
     better_html (1.0.16)
       actionview (>= 4.0)
       activesupport (>= 4.0)
@@ -373,8 +377,10 @@ PLATFORMS
   universal-java-11
 
 DEPENDENCIES
+  activerecord-explain-analyze
   activerecord-jdbcpostgresql-adapter
   appraisal!
+  benchmark-ips (= 2.8.4)
   capybara
   database_cleaner
   dotenv

good_job.gemspec

@@ -54,6 +54,8 @@ Gem::Specification.new do |spec|
   spec.add_dependency "thor", ">= 0.14.1"
   spec.add_dependency "zeitwerk", ">= 2.0"
 
+  spec.add_development_dependency "activerecord-explain-analyze"
+  spec.add_development_dependency "benchmark-ips", "2.8.4" # https://github.com/evanphx/benchmark-ips/pull/115
   spec.add_development_dependency "capybara"
   spec.add_development_dependency "database_cleaner"
   spec.add_development_dependency "dotenv"

scripts/benchmark_job_throughput.rb

@@ -0,0 +1,51 @@
+# To run:
+# bundle exec ruby scripts/benchmark_example.rb
+#
+
+ENV['GOOD_JOB_EXECUTION_MODE'] = 'external'
+
+require_relative '../spec/test_app/config/environment'
+require_relative '../lib/good_job'
+require 'benchmark/ips'
+require 'pry'
+
+booleans = [true, false]
+priorities = (1..10).to_a
+scheduled_minutes = (-60..60).to_a
+
+GoodJob::Job.delete_all
+puts "Seeding database"
+jobs_data = Array.new(10_000) do |i|
+  puts "Initializing seed record ##{i}" if (i % 1_000).zero?
+  {
+    queue_name: 'default',
+    priority: priorities.sample,
+    scheduled_at: booleans.sample ? scheduled_minutes.sample.minutes.ago : nil,
+    created_at: 90.minutes.ago,
+    updated_at: 90.minutes.ago,
+    finished_at: booleans.sample ? scheduled_minutes.sample.minutes.ago : nil,
+    serialized_params: {},
+  }
+end
+puts "Inserting seed records into the database...\n"
+GoodJob::Job.insert_all(jobs_data)
+
+# ActiveRecord::Base.connection.execute('SET enable_seqscan = OFF')
+# puts GoodJob::Job.unfinished.priority_ordered.only_scheduled(use_coalesce: true).limit(1).advisory_lock.explain(analyze: true)
+# exit!
+
+Benchmark.ips do |x|
+  x.report("with priority") do
+    GoodJob::Job.unfinished.priority_ordered.only_scheduled(use_coalesce: true).limit(1).with_advisory_lock do |good_jobs|
+      # good_jobs.first&.destroy!
+    end
+  end
+
+  x.report("without priority") do
+    GoodJob::Job.unfinished.only_scheduled(use_coalesce: true).limit(1).with_advisory_lock do |good_jobs|
+      # good_jobs.first&.destroy!
+    end
+  end
+
+  x.compare!
+end