diff --git a/app/controllers/admin/background_jobs_controller.rb b/app/controllers/admin/background_jobs_controller.rb
index c09095b9849..87eb7ff4c93 100644
--- a/app/controllers/admin/background_jobs_controller.rb
+++ b/app/controllers/admin/background_jobs_controller.rb
@@ -1,6 +1,6 @@
 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))
+    ps_output, _ = Gitlab::Popen.popen(%W(ps ww -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
diff --git a/changelogs/unreleased/fix_rake_gitlab_check_sidekiq.yml b/changelogs/unreleased/fix_rake_gitlab_check_sidekiq.yml
new file mode 100644
index 00000000000..4752ed34ae6
--- /dev/null
+++ b/changelogs/unreleased/fix_rake_gitlab_check_sidekiq.yml
@@ -0,0 +1,4 @@
+---
+title: Force unlimited terminal size when checking processes via call to ps
+merge_request: 10246
+author: Sebastian Reitenbach
diff --git a/lib/tasks/gitlab/check.rake b/lib/tasks/gitlab/check.rake
index a6f8c4ced5d..a9a48f7188f 100644
--- a/lib/tasks/gitlab/check.rake
+++ b/lib/tasks/gitlab/check.rake
@@ -617,7 +617,7 @@ namespace :gitlab do
     end
 
     def sidekiq_process_count
-      ps_ux, _ = Gitlab::Popen.popen(%w(ps ux))
+      ps_ux, _ = Gitlab::Popen.popen(%w(ps uxww))
       ps_ux.scan(/sidekiq \d+\.\d+\.\d+/).count
     end
   end
@@ -751,7 +751,7 @@ namespace :gitlab do
     end
 
     def mail_room_running?
-      ps_ux, _ = Gitlab::Popen.popen(%w(ps ux))
+      ps_ux, _ = Gitlab::Popen.popen(%w(ps uxww))
       ps_ux.include?("mail_room")
     end
   end