chore: benchmark for parallel deletion

Makefile

@@ -130,6 +130,13 @@ benchmark:
 		'gdu -npc ~' 'gdu -gnpc ~' 'gdu -npc --use-storage ~'
 	sudo cpupower frequency-set -g schedutil
 
+benchmark-deletion:
+	hyperfine \
+		--export-markdown=bench-delete.md \
+		--prepare 'cd test; git init . ; fallocate -l 1G .git/info/file ; dd if=/dev/urandom of=.git/refs/file bs=64M count=8 iflag=fullblock ; dd if=/dev/urandom of=.git/objects/file bs=64M count=8 iflag=fullblock ; cd ..' \
+		'go run ./cmd/deleter/main.go ./test/.git' \
+		'go run ./cmd/deleter/main.go --parallel ./test/.git'
+
 clean:
 	go mod tidy
 	-rm coverage.txt

bench-delete.md

@@ -0,0 +1,4 @@
+| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
+|:---|---:|---:|---:|---:|
+| `go run ./cmd/deleter/main.go ./test/.git` | 840.3 ± 648.5 | 504.2 | 2137.6 | 1.00 |
+| `go run ./cmd/deleter/main.go --parallel ./test/.git` | 902.1 ± 885.1 | 476.1 | 3168.0 | 1.07 ± 1.34 |

cmd/deleter/main.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"runtime/trace"
+	"time"
+
+	"github.com/dundee/gdu/v5/pkg/fs"
+	"github.com/dundee/gdu/v5/pkg/remove"
+)
+
+func main() {
+	inParallel := flag.Bool("parallel", false, "Delete in parallel")
+	tracing := flag.Bool("trace", false, "Collect CPU trace")
+	flag.Parse()
+	args := flag.Args()
+
+	if len(args) < 1 {
+		fmt.Println("Usage: [--parallel] directory_to_delete")
+		return
+	}
+
+	if info, err := os.Stat(args[0]); os.IsNotExist(err) {
+		fmt.Println("Path does not exist")
+		return
+	} else if !info.IsDir() {
+		fmt.Println("Path is not directory")
+		return
+	}
+	path, err := filepath.Abs(args[0])
+	if err != nil {
+		fmt.Println("Cannot convert to absolute: ", err.Error())
+	}
+
+	deleter := remove.RemoveItemFromDir
+	if *inParallel {
+		deleter = remove.RemoveItemFromDirParallel
+	}
+
+	if *tracing {
+		f, err := os.Create("trace.out")
+		if err != nil {
+			fmt.Println("Trace file cannot be created: ", err.Error())
+			return
+		}
+		trace.Start(f)
+	}
+
+	err = deleter(NewDeletedItem(""), NewDeletedItem(path))
+	if err != nil {
+		fmt.Println("Failed with: ", err.Error())
+	}
+	trace.Stop()
+}
+
+func NewDeletedItem(path string) fs.Item {
+	return &DeletedItem{
+		Path: path,
+	}
+}
+
+type DeletedItem struct {
+	Path string
+}
+
+func (p *DeletedItem) GetPath() string {
+	return p.Path
+}
+func (p *DeletedItem) GetFilesLocked() fs.Files {
+	var items []fs.Item
+	entries, err := os.ReadDir(p.Path)
+	if err != nil {
+		panic(err)
+	}
+
+	for _, entry := range entries {
+		path := filepath.Join(p.Path, entry.Name())
+		items = append(items, NewDeletedItem(path))
+	}
+	return items
+}
+func (p *DeletedItem) IsDir() bool             { return true }
+func (f *DeletedItem) RemoveFile(item fs.Item) {}
+
+func (p *DeletedItem) GetName() string                                  { panic("must not be called") }
+func (p *DeletedItem) GetFlag() rune                                    { panic("must not be called") }
+func (p *DeletedItem) GetSize() int64                                   { panic("must not be called") }
+func (p *DeletedItem) GetType() string                                  { panic("must not be called") }
+func (p *DeletedItem) GetUsage() int64                                  { panic("must not be called") }
+func (p *DeletedItem) GetMtime() time.Time                              { panic("must not be called") }
+func (p *DeletedItem) GetItemCount() int                                { panic("must not be called") }
+func (p *DeletedItem) GetParent() fs.Item                               { panic("must not be called") }
+func (p *DeletedItem) SetParent(fs.Item)                                { panic("must not be called") }
+func (p *DeletedItem) GetMultiLinkedInode() uint64                      { panic("must not be called") }
+func (p *DeletedItem) EncodeJSON(writer io.Writer, topLevel bool) error { panic("must not be called") }
+func (p *DeletedItem) UpdateStats(linkedItems fs.HardLinkedItems)       { panic("must not be called") }
+func (p *DeletedItem) AddFile(fs.Item)                                  { panic("must not be called") }
+func (p *DeletedItem) GetFiles() fs.Files                               { panic("must not be called") }
+func (p *DeletedItem) RLock() func()                                    { panic("must not be called") }
+func (p *DeletedItem) SetFiles(fs.Files)                                { panic("must not be called") }
+func (p *DeletedItem) GetItemStats(
+	linkedItems fs.HardLinkedItems,
+) (int, int64, int64) {
+	panic("must not be called")
+}