Don't remove pidfile on exit, #1677

Changes.md

@@ -1,6 +1,8 @@
 HEAD
 -----------
 
+- Revert pidfile behavior from 2.17.5: Sidekiq will no longer remove its own pidfile
+  as this is a race condition when restarting. [#1470, #1677]
 - Show warning on the Queues page if a queue is paused [#1672]
 - Only activate the ActiveRecord middleware if ActiveRecord::Base is defined on boot. [#1666]
 - Add ability to disable jobs going to the DJQ with the `dead` option.

lib/sidekiq/cli.rb

@@ -324,9 +324,6 @@ module Sidekiq
         File.open(pidfile, 'w') do |f|
           f.puts Process.pid
         end
-        at_exit do
-          FileUtils.rm_f pidfile
-        end
       end
     end