More performant strand unblocker (#36)

* More performant strand unblocker

* Drop support for EOL rails 7.0

Author: maths22

.github/workflows/continuous_integration.yml

@@ -21,7 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         ruby: ['3.1', '3.2', '3.3', '3.4']
-        lockfile: ['activerecord-7.0', 'activerecord-7.1', 'Gemfile.lock']
+        lockfile: ['activerecord-7.1', 'Gemfile.lock']
 
     services:
       postgres:

Gemfile

@@ -25,15 +25,6 @@ gem "rubocop-rspec", "~> 3.0", require: false
 gem "simplecov", "~> 0.21", require: false
 gem "zeitwerk", "~> 2.6", "< 2.7", require: false
 
-lockfile "activerecord-7.0" do
-  gem "activerecord", "~> 7.0.0"
-  gem "base64", "~> 0.1", require: RUBY_VERSION >= "3.4.0"
-  gem "bigdecimal", "~> 3.1", require: RUBY_VERSION >= "3.4.0"
-  gem "drb", "~> 2.1", require: RUBY_VERSION >= "3.4.0"
-  gem "mutex_m", "~> 0.1", require: RUBY_VERSION >= "3.4.0"
-  gem "railties", "~> 7.0.0"
-end
-
 lockfile "activerecord-7.1" do
   gem "activerecord", "~> 7.1.0"
   gem "activerecord-pg-extensions", "~> 0.5"

Gemfile.activerecord-7.0.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    switchman-inst-jobs (4.1.0)
+    switchman-inst-jobs (4.2.0)
       inst-jobs (>= 2.4.9, < 4.0)
       parallel (>= 1.19)
       railties (>= 7.0, < 8.0)

Gemfile.activerecord-7.1.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    switchman-inst-jobs (4.1.0)
+    switchman-inst-jobs (4.2.0)
       inst-jobs (>= 2.4.9, < 4.0)
       parallel (>= 1.19)
       railties (>= 7.0, < 8.0)

Gemfile.lock

@@ -230,14 +230,16 @@ def unblock_strands(target_shard, batch_size: 10_000)
         blocked_shard_ids = blocked_shards.pluck(:id)
         query = lambda { |column, scope|
           ::Delayed::Job
-            .where(id: ::Delayed::Job.select("DISTINCT ON (#{column}) id")
-              .where(scope)
+            .where(id: ::Delayed::Job
+              .with(all_col: ::Delayed::Job.and(scope).distinct.select(column))
+              .with(blocked_col: ::Delayed::Job.from("all_col").select(column).where.not(
+                ::Delayed::Job.select(1)
+                  .where(next_in_strand: true).or(::Delayed::Job.where(source: "JobsMigrator::StrandBlocker"))
+                  .where("#{column} = all_col.#{column}").arel.exists
+              ))
+              .select("DISTINCT ON (#{column}) id")
               .where.not(shard_id: blocked_shard_ids)
-              .where(
-                ::Delayed::Job.select(1).from("#{::Delayed::Job.quoted_table_name} dj2")
-                .where("dj2.next_in_strand = true OR dj2.source = 'JobsMigrator::StrandBlocker'")
-                .where("dj2.#{column} = delayed_jobs.#{column}").arel.exists.not
-              )
+              .where({ column => ::Delayed::Job.from("blocked_col").select(column) })
               .order(column, :strand_order_override, :id)).limit(batch_size)
         }
 
@@ -249,12 +251,13 @@ def unblock_strands(target_shard, batch_size: 10_000)
           # batches
 
           loop do
-            break if query.call(:strand, "strand IS NOT NULL").update_all(next_in_strand: true).zero?
+            break if query.call(:strand, ::Delayed::Job.where.not(strand: nil)).update_all(next_in_strand: true).zero?
           end
 
           loop do
             break if query.call(:singleton,
-                                "strand IS NULL AND singleton IS NOT NULL").update_all(next_in_strand: true).zero?
+                                ::Delayed::Job.where(strand: nil)
+                                .where.not(singleton: nil)).update_all(next_in_strand: true).zero?
           end
         end
       end

lib/switchman_inst_jobs/jobs_migrator.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module SwitchmanInstJobs
-  VERSION = "4.1.0"
+  VERSION = "4.2.0"
 end