fix incorrect sidekiq concurrency count in admin background page

app/controllers/admin/background_jobs_controller.rb

@@ -2,5 +2,6 @@ class Admin::BackgroundJobsController < Admin::ApplicationController
   def show
     ps_output, _ = Gitlab::Popen.popen(%W(ps -U #{Gitlab.config.gitlab.user} -o pid,pcpu,pmem,stat,start,command))
     @sidekiq_processes = ps_output.split("\n").grep(/sidekiq/)
+    @concurrency = Sidekiq.options[:concurrency]
   end
 end

app/views/admin/background_jobs/show.html.haml

@@ -35,7 +35,7 @@
         .clearfix
           %p
             %i.fa.fa-exclamation-circle
-            If '[25 of 25 busy]' is shown, restart GitLab with 'sudo service gitlab reload'.
+            = "If '[#{@concurrency} of #{@concurrency} busy]' is shown, restart GitLab with 'sudo service gitlab reload'."
           %p
             %i.fa.fa-exclamation-circle
             If more than one sidekiq process is listed, stop GitLab, kill the remaining sidekiq processes (sudo pkill -u #{gitlab_config.user} -f sidekiq) and restart GitLab.

changelogs/unreleased/fix_sidekiq_concurrency_warning_message_in_admin_background_job_page.yml

@@ -0,0 +1,4 @@
+---
+title: fix incorrect sidekiq concurrency count in admin background page
+merge_request:
+author: wendy0402