Optimize bulk unlocking

CHANGELOG.md

@@ -5,6 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [Unreleased](https://github.com/veeqo/activejob-uniqueness/compare/v0.3.2...HEAD)
 
+### Changed
+- [#82](https://github.com/veeqo/activejob-uniqueness/pull/82) Optimize bulk unlocking [@sharshenov](https://github.com/sharshenov)
+
 ## [0.3.2](https://github.com/veeqo/activejob-uniqueness/compare/v0.3.1...v0.3.2) - 2024-08-16
 
 ### Added

lib/active_job/uniqueness/lock_manager.rb

@@ -17,11 +17,17 @@ def delete_lock(resource)
         true
       end
 
+      DELETE_LOCKS_SCAN_COUNT = 1000
+
       # Unlocks multiple resources by key wildcard.
       def delete_locks(wildcard)
         @servers.each do |server|
           synced_redis_connection(server) do |conn|
-            conn.scan('MATCH', wildcard).each { |key| conn.call('DEL', key) }
+            cursor = 0
+            while cursor != '0'
+              cursor, keys = conn.call('SCAN', cursor, 'MATCH', wildcard, 'COUNT', DELETE_LOCKS_SCAN_COUNT)
+              conn.call('DEL', *keys) unless keys.empty?
+            end
           end
         end
 

spec/active_job/uniqueness/unlock_spec.rb

@@ -68,4 +68,26 @@
       end
     end
   end
+
+  describe 'bulk deletion' do
+    subject(:unlock!) { described_class.unlock! }
+
+    let(:expected_initial_number_of_locks) { 1_103 } # 1_100 + 2 + 1
+    let(:expected_number_of_delete_commands) { 2 } # 1103 / 1000 (ActiveJob::Uniqueness::LockManager::DELETE_LOCKS_SCAN_COUNT)
+
+    before { 1_100.times.each { |i| job_class.perform_later(3, i) } }
+
+    it 'removes locks efficiently' do
+      expect { unlock! }.to change { locks_count }.from(expected_initial_number_of_locks).to(0)
+                        .and change { delete_commands_calls }.by(expected_number_of_delete_commands)
+    end
+
+    def delete_commands_calls
+      info = redis.call('INFO', 'commandstats')
+      del_stats = info.split("\n").find { |line| line.start_with?('cmdstat_del:') }
+      return 0 unless del_stats
+
+      del_stats.match(/cmdstat_del:calls=(\d+)/)[1].to_i
+    end
+  end
 end