Log number of Sidekiq jobs scheduled by set

Both the retry set and the scheduled set can have jobs enqueued, so it
would be good to split those in the logs. The scheduled set will have
many more jobs, so overall figures will be representative of that set
anyway.

lib/gitlab/sidekiq_enq.rb

@@ -11,14 +11,15 @@
 module Gitlab
   class SidekiqEnq
     def enqueue_jobs(now = Time.now.to_f.to_s, sorted_sets = Sidekiq::Scheduled::SETS)
-      start_time = ::Gitlab::Metrics::System.monotonic_time
-      jobs = redundant_jobs = 0
-      Sidekiq.logger.info(message: 'Enqueuing scheduled jobs', status: 'start')
-
       # A job's "score" in Redis is the time at which it should be processed.
       # Just check Redis for the set of jobs with a timestamp before now.
       Sidekiq.redis do |conn|
         sorted_sets.each do |sorted_set|
+          start_time = ::Gitlab::Metrics::System.monotonic_time
+          jobs = redundant_jobs = 0
+
+          Sidekiq.logger.info(message: 'Enqueuing scheduled jobs', status: 'start', sorted_set: sorted_set)
+
           # Get the next item in the queue if it's score (time to execute) is <= now.
           # We need to go through the list one at a time to reduce the risk of something
           # going wrong between the time jobs are popped from the scheduled queue and when
@@ -35,11 +36,16 @@ module Gitlab
               redundant_jobs += 1
             end
           end
+
+          end_time = ::Gitlab::Metrics::System.monotonic_time
+          Sidekiq.logger.info(message: 'Enqueuing scheduled jobs',
+                              status: 'done',
+                              sorted_set: sorted_set,
+                              jobs_count: jobs,
+                              redundant_jobs_count: redundant_jobs,
+                              duration_s: end_time - start_time)
         end
       end
-
-      end_time = ::Gitlab::Metrics::System.monotonic_time
-      Sidekiq.logger.info(message: 'Enqueuing scheduled jobs', status: 'done', jobs_count: jobs, redundant_jobs_count: redundant_jobs, duration_s: end_time - start_time)
     end
   end
 end