feat: delete directory items in parallel

README.md

@@ -180,6 +180,22 @@ style:
         background-color: "#ff0000"
 ```
 
+## Deletion in background and in parallel (experimental)
+
+Gdu can delete items in the background, thus not blocking the UI for additional work.
+To enable:
+
+```
+echo "delete-in-background: true" >> ~/.gdu.yaml
+```
+
+Directory items can be also deleted in parallel, which can increase the speed of deletion.
+To enable:
+
+```
+echo "delete-in-parallel: true" >> ~/.gdu.yaml
+```
+
 ## Memory usage
 
 ### Automatic balancing

cmd/gdu/app/app.go

@@ -76,6 +76,7 @@
 	WriteConfig        bool     `yaml:"-"`
 	ChangeCwd          bool     `yaml:"change-cwd"`
 	DeleteInBackground bool     `yaml:"delete-in-background"`
+	DeleteInParallel   bool     `yaml:"delete-in-parallel"`
 	Style              Style    `yaml:"style"`
 	Sorting            Sorting  `yaml:"sorting"`
 }
@@ -286,6 +287,11 @@
 				ui.SetDeleteInBackground()
 			})
 		}
+		if a.Flags.DeleteInParallel {
+			opts = append(opts, func(ui *tui.UI) {
+				ui.SetDeleteInParallel()
+			})
+		}
 
 		ui = tui.CreateUI(
 			a.TermApp,

internal/testanalyze/analyze.go

@@ -7,6 +7,7 @@ import (
 	"github.com/dundee/gdu/v5/internal/common"
 	"github.com/dundee/gdu/v5/pkg/analyze"
 	"github.com/dundee/gdu/v5/pkg/fs"
+	"github.com/dundee/gdu/v5/pkg/remove"
 )
 
 // MockedAnalyzer returns dir with files with different size exponents
@@ -91,7 +92,7 @@ func RemoveItemFromDirWithErr(dir fs.Item, file fs.Item) error {
 // RemoveItemFromDirWithSleep returns error
 func RemoveItemFromDirWithSleep(dir fs.Item, file fs.Item) error {
 	time.Sleep(time.Millisecond * 600)
-	return analyze.RemoveItemFromDir(dir, file)
+	return remove.RemoveItemFromDir(dir, file)
 }
 
 // RemoveItemFromDirWithSleepAndErr returns error

pkg/analyze/file.go

@@ -1,7 +1,6 @@
 package analyze
 
 import (
-	"os"
 	"path/filepath"
 	"sync"
 	"time"
@@ -231,7 +230,7 @@ func (f *Dir) UpdateStats(linkedItems fs.HardLinkedItems) {
 	f.Usage = totalUsage
 }
 
-// RemoveFile panics on file
+// RemoveFile removes item from dir, updates size and item count
 func (f *Dir) RemoveFile(item fs.Item) {
 	f.m.Lock()
 	defer f.m.Unlock()
@@ -256,44 +255,3 @@ func (f *Dir) RLock() func() {
 	f.m.RLock()
 	return f.m.RUnlock
 }
-
-// RemoveItemFromDir removes item from dir
-func RemoveItemFromDir(dir fs.Item, item fs.Item) error {
-	err := os.RemoveAll(item.GetPath())
-	if err != nil {
-		return err
-	}
-
-	dir.RemoveFile(item)
-	return nil
-}
-
-// EmptyFileFromDir empty file from dir
-func EmptyFileFromDir(dir fs.Item, file fs.Item) error {
-	err := os.Truncate(file.GetPath(), 0)
-	if err != nil {
-		return err
-	}
-
-	cur := dir.(*Dir)
-	for {
-		cur.Size -= file.GetSize()
-		cur.Usage -= file.GetUsage()
-
-		if cur.Parent == nil {
-			break
-		}
-		cur = cur.Parent.(*Dir)
-	}
-
-	dir.SetFiles(dir.GetFiles().Remove(file))
-	newFile := &File{
-		Name:   file.GetName(),
-		Flag:   file.GetFlag(),
-		Size:   0,
-		Parent: dir,
-	}
-	dir.AddFile(newFile)
-
-	return nil
-}

pkg/analyze/file_test.go

@@ -4,7 +4,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/dundee/gdu/v5/internal/testdir"
 	"github.com/dundee/gdu/v5/pkg/fs"
 	"github.com/stretchr/testify/assert"
 )
@@ -201,125 +200,6 @@ func TestRemoveByNameNotInDir(t *testing.T) {
 	assert.Equal(t, 1, len(dir.Files))
 }
 
-func TestRemoveFile(t *testing.T) {
-	dir := &Dir{
-		File: &File{
-			Name:  "xxx",
-			Size:  5,
-			Usage: 12,
-		},
-		ItemCount: 3,
-		BasePath:  ".",
-	}
-
-	subdir := &Dir{
-		File: &File{
-			Name:   "yyy",
-			Size:   4,
-			Usage:  8,
-			Parent: dir,
-		},
-		ItemCount: 2,
-	}
-	file := &File{
-		Name:   "zzz",
-		Size:   3,
-		Usage:  4,
-		Parent: subdir,
-	}
-	dir.Files = fs.Files{subdir}
-	subdir.Files = fs.Files{file}
-
-	err := RemoveItemFromDir(subdir, file)
-	assert.Nil(t, err)
-
-	assert.Equal(t, 0, len(subdir.Files))
-	assert.Equal(t, 1, subdir.ItemCount)
-	assert.Equal(t, int64(1), subdir.Size)
-	assert.Equal(t, int64(4), subdir.Usage)
-	assert.Equal(t, 1, len(dir.Files))
-	assert.Equal(t, 2, dir.ItemCount)
-	assert.Equal(t, int64(2), dir.Size)
-}
-
-func TestTruncateFile(t *testing.T) {
-	fin := testdir.CreateTestDir()
-	defer fin()
-
-	dir := &Dir{
-		File: &File{
-			Name:  "test_dir",
-			Size:  5,
-			Usage: 12,
-		},
-		ItemCount: 3,
-		BasePath:  ".",
-	}
-
-	subdir := &Dir{
-		File: &File{
-			Name:   "nested",
-			Size:   4,
-			Usage:  8,
-			Parent: dir,
-		},
-		ItemCount: 2,
-	}
-	file := &File{
-		Name:   "file2",
-		Size:   3,
-		Usage:  4,
-		Parent: subdir,
-	}
-	dir.Files = fs.Files{subdir}
-	subdir.Files = fs.Files{file}
-
-	err := EmptyFileFromDir(subdir, file)
-
-	assert.Nil(t, err)
-	assert.Equal(t, 1, len(subdir.Files))
-	assert.Equal(t, 2, subdir.ItemCount)
-	assert.Equal(t, int64(1), subdir.Size)
-	assert.Equal(t, int64(4), subdir.Usage)
-	assert.Equal(t, 1, len(dir.Files))
-	assert.Equal(t, 3, dir.ItemCount)
-	assert.Equal(t, int64(2), dir.Size)
-}
-
-func TestTruncateFileWithErr(t *testing.T) {
-	dir := &Dir{
-		File: &File{
-			Name:  "xxx",
-			Size:  5,
-			Usage: 12,
-		},
-		ItemCount: 3,
-		BasePath:  ".",
-	}
-
-	subdir := &Dir{
-		File: &File{
-			Name:   "yyy",
-			Size:   4,
-			Usage:  8,
-			Parent: dir,
-		},
-		ItemCount: 2,
-	}
-	file := &File{
-		Name:   "zzz",
-		Size:   3,
-		Usage:  4,
-		Parent: subdir,
-	}
-	dir.Files = fs.Files{subdir}
-	subdir.Files = fs.Files{file}
-
-	err := EmptyFileFromDir(subdir, file)
-
-	assert.Contains(t, err.Error(), "no such file or directory")
-}
-
 func TestUpdateStats(t *testing.T) {
 	dir := Dir{
 		File: &File{

pkg/analyze/stored.go

@@ -282,7 +282,8 @@ func (f *StoredDir) SetFiles(files fs.Files) {
 	f.Files = files
 }
 
-// RemoveFile panics on file
+// RemoveFile removes file from stored directory
+// It also updates size and item count of parent directories
 func (f *StoredDir) RemoveFile(item fs.Item) {
 	if !DefaultStorage.IsOpen() {
 		f.dbLock.Lock()

pkg/remove/parallel.go

@@ -0,0 +1,58 @@
+package remove
+
+import (
+	"os"
+	"runtime"
+	"sync"
+
+	"github.com/dundee/gdu/v5/pkg/fs"
+)
+
+var concurrencyLimit = make(chan struct{}, 3*runtime.GOMAXPROCS(0))
+
+// RemoveItemFromDirParallel removes item from dir
+func RemoveItemFromDirParallel(dir fs.Item, item fs.Item) error {
+	if !item.IsDir() {
+		return RemoveItemFromDir(dir, item)
+	}
+	errChan := make(chan error, 1) // we show only first error
+	var wait sync.WaitGroup
+
+	// remove all files in the directory in parallel
+	for _, file := range item.GetFilesLocked() {
+		wait.Add(1)
+		go func(itemPath string) {
+			concurrencyLimit <- struct{}{}
+			defer func() { <-concurrencyLimit }()
+
+			err := os.RemoveAll(itemPath)
+			if err != nil {
+				select {
+				// write error to channel if it's empty
+				case errChan <- err:
+				default:
+				}
+			}
+			wait.Done()
+		}(file.GetPath())
+	}
+
+	wait.Wait()
+
+	// check if there was an error
+	select {
+	case err := <-errChan:
+		return err
+	default:
+	}
+
+	// remove the directory itself
+	err := os.RemoveAll(item.GetPath())
+	if err != nil {
+		return err
+	}
+
+	// update parent directory
+	dir.RemoveFile(item)
+	return nil
+}

pkg/remove/parallel_linux_test.go

@@ -0,0 +1,67 @@
+//go:build linux
+// +build linux
+
+package remove
+
+import (
+	"os"
+	"testing"
+
+	"github.com/dundee/gdu/v5/internal/testdir"
+	"github.com/dundee/gdu/v5/pkg/analyze"
+	"github.com/dundee/gdu/v5/pkg/fs"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRemoveItemFromDirParallelWithErr(t *testing.T) {
+	fin := testdir.CreateTestDir()
+	defer fin()
+
+	err := os.Chmod("test_dir/nested", 0)
+	assert.Nil(t, err)
+	defer func() {
+		err = os.Chmod("test_dir/nested", 0755)
+		assert.Nil(t, err)
+	}()
+
+	dir := &analyze.Dir{
+		File: &analyze.File{
+			Name: "test_dir",
+		},
+		BasePath: ".",
+	}
+
+	subdir := &analyze.Dir{
+		File: &analyze.File{
+			Name:   "nested",
+			Parent: dir,
+		},
+	}
+
+	err = RemoveItemFromDirParallel(dir, subdir)
+	assert.Contains(t, err.Error(), "permission denied")
+}
+
+func TestRemoveItemFromDirParallelWithErr2(t *testing.T) {
+	fin := testdir.CreateTestDir()
+	defer fin()
+
+	err := os.Chmod("test_dir/nested/subnested", 0)
+	assert.Nil(t, err)
+	defer func() {
+		err = os.Chmod("test_dir/nested/subnested", 0755)
+		assert.Nil(t, err)
+	}()
+
+	analyzer := analyze.CreateAnalyzer()
+	dir := analyzer.AnalyzeDir(
+		"test_dir", func(_, _ string) bool { return false }, false,
+	).(*analyze.Dir)
+	analyzer.GetDone().Wait()
+	dir.UpdateStats(make(fs.HardLinkedItems))
+
+	subdir := dir.Files[0].(*analyze.Dir)
+
+	err = RemoveItemFromDirParallel(dir, subdir)
+	assert.Contains(t, err.Error(), "permission denied")
+}