clear worker set upon clean shutdown, fixes #840

lib/sidekiq/manager.rb

@@ -42,6 +42,8 @@ module Sidekiq
         @ready.each { |x| x.terminate if x.alive? }
         @ready.clear
 
+        clear_worker_set
+
         return after(0) { signal(:shutdown) } if @busy.empty?
         hard_shutdown_in timeout if shutdown
       end
@@ -107,6 +109,21 @@ module Sidekiq
 
     private
 
+    def clear_worker_set
+      # Clearing workers in Redis
+      # NOTE: we do this before terminating worker threads because the
+      # process will likely receive a hard shutdown soon anyway, which
+      # means the threads will killed.
+      logger.debug { "Clearing workers in redis" }
+      Sidekiq.redis do |conn|
+        workers = conn.smembers('workers')
+        workers_to_remove = workers.select do |worker_name|
+          worker_name =~ /:#{process_id}-/
+        end
+        conn.srem('workers', workers_to_remove) if !workers_to_remove.empty?
+      end
+    end
+
     def hard_shutdown_in(delay)
       logger.info { "Pausing up to #{delay} seconds to allow workers to finish..." }
 
@@ -124,19 +141,6 @@ module Sidekiq
           # it is worse to lose a job than to run it twice.
           Sidekiq::Fetcher.strategy.bulk_requeue(@in_progress.values)
 
-          # Clearing workers in Redis
-          # NOTE: we do this before terminating worker threads because the
-          # process will likely receive a hard shutdown soon anyway, which
-          # means the threads will killed.
-          logger.debug { "Clearing workers in redis" }
-          Sidekiq.redis do |conn|
-            workers = conn.smembers('workers')
-            workers_to_remove = workers.select do |worker_name|
-              worker_name =~ /:#{process_id}-/
-            end
-            conn.srem('workers', workers_to_remove) if !workers_to_remove.empty?
-          end
-
           logger.debug { "Terminating worker threads" }
           @busy.each do |processor|
             t = processor.bare_object.actual_work_thread