PERF: restart sidekiq if it consumes more than 500MB

configurable with UNICORN_SIDEKIQ_MAX_RSS

config/unicorn.conf.rb

@@ -80,19 +80,39 @@ before_fork do |server, worker|
       class ::Unicorn::HttpServer
         alias :master_sleep_orig :master_sleep
 
+        def max_rss
+          `ps -eo rss,args | grep sidekiq | grep -v grep | awk '{print $1}'`
+                .split("\n")
+                .map(&:to_i)
+                .max * 1024
+        end
+
+        def out_of_memory?
+          max_allowed_size = [ENV['UNICORN_SIDEKIQ_MAX_RSS'].to_i, 500].min;
+          max_rss > max_allowed_size
+        end
+
         def check_sidekiq_heartbeat
           @sidekiq_heartbeat_interval ||= 30.minutes
           @sidekiq_next_heartbeat_check ||= Time.new.to_i + @sidekiq_heartbeat_interval
 
           if @sidekiq_next_heartbeat_check < Time.new.to_i
+
             last_heartbeat = Jobs::RunHeartbeat.last_heartbeat
+            if out_of_memory?
+              Rails.logger.warn("Sidekiq is consuming too much memory (using: %0.2fM), restarting" % (max_rss.to_f / 1.megabyte))
+              Demon::Sidekiq.restart
+            end
+
             if last_heartbeat < Time.new.to_i - @sidekiq_heartbeat_interval
               STDERR.puts "Sidekiq heartbeat test failed, restarting"
-              puts "Sidekiq heartbeat test failed, restarting"
+              Rails.logger.warn "Sidekiq heartbeat test failed, restarting"
 
               Demon::Sidekiq.restart
             end
             @sidekiq_next_heartbeat_check = Time.new.to_i + @sidekiq_heartbeat_interval
+
+            $redis.client.disconnect
           end
         end