Resolve "Impossible to remove orphan artifact files"

changelogs/unreleased/211950-impossible-to-remove-orphan-artifact-files.yml

+---
+title: Fix invalid class option for ionice
+merge_request: 28023
+author:
+type: fixed

lib/gitlab/cleanup/orphan_job_artifact_files.rb

@@ -102,7 +102,7 @@ module Gitlab
           if ionice
             raise ArgumentError, 'Invalid niceness' unless VALID_NICENESS_LEVELS.include?(niceness)
 
-            cmd.unshift(*%W[#{ionice} --class #{niceness}])
+            cmd.unshift(*%W[#{ionice} -c #{niceness}])
           end
 
           log_info("find command: '#{cmd.join(' ')}'")

spec/lib/gitlab/cleanup/orphan_job_artifact_files_spec.rb

@@ -28,6 +28,12 @@ describe Gitlab::Cleanup::OrphanJobArtifactFiles do
     expect { cleanup.run! }.to raise_error('Invalid niceness')
   end
 
+  it 'passes correct arguments to ionice' do
+    allow(Gitlab::Utils).to receive(:which).with('ionice').and_return('/fake/ionice')
+    expect(Open3).to receive(:popen3).with('/fake/ionice', '-c', any_args)
+    cleanup.run!
+  end
+
   it 'finds artifacts on disk' do
     artifact = create(:ci_job_artifact, :archive)