Set a low IO priority for storage moves to lower performance impact

CHANGELOG

+v3.6.1
+  - Set a low IO priority for storage moves to lower performance impact
+
 v3.6.0
   - Added full support for `git-lfs-authenticate` to properly handle LFS requests and pass them on to Workhorse
 

lib/gitlab_projects.rb

@@ -316,7 +316,17 @@ class GitlabProjects
 
     if wait_for_pushes
       $logger.info "Syncing project #{@project_name} from <#{full_path}> to <#{new_full_path}>."
-      system(*%W(rsync -a --delete #{source_path} #{new_full_path}))
+
+      # Set a low IO priority with ionice to not choke the server on moves
+      rsync_path = 'ionice -c2 -n7 rsync'
+      result = system(*%W(#{rsync_path} -a --delete --rsync-path="#{rsync_path}" #{source_path} #{new_full_path}))
+
+      unless result
+        # If the command fails with `ionice` (maybe because we're on a OS X
+        # development machine), try again without `ionice`.
+        rsync_path = 'rsync'
+        system(*%W(#{rsync_path} -a --delete --rsync-path="#{rsync_path}" #{source_path} #{new_full_path}))
+      end
     else
       $logger.error "mv-storage failed: source path <#{full_path}> is waiting for pushes to finish."
       false

spec/gitlab_projects_spec.rb

@@ -212,6 +212,7 @@ describe GitlabProjects do
 
     before do
       FileUtils.mkdir_p(tmp_repo_path)
+      FileUtils.mkdir_p(File.join(tmp_repo_path, 'hooks')) # Add some contents to copy
       FileUtils.mkdir_p(alternative_storage_path)
       allow_any_instance_of(GitlabReferenceCounter).to receive(:value).and_return(0)
     end
@@ -222,6 +223,8 @@ describe GitlabProjects do
       File.exists?(tmp_repo_path).should be_true
       gl_projects.exec
       File.exists?(new_repo_path).should be_true
+      # Make sure the target directory isn't empty (i.e. contents were copied)
+      FileUtils.cd(new_repo_path) { Dir['**/*'].length.should_not be(0) }
     end
 
     it "should fail if no destination path is provided" do