info recursively support fast mode

cmd/info.go

@@ -59,6 +59,11 @@ $ juicefs info -i 100`,
 				Aliases: []string{"r"},
 				Usage:   "get summary of directories recursively (NOTE: it may take a long time for huge trees)",
 			},
+			&cli.BoolFlag{
+				Name:    "fast",
+				Aliases: []string{"f"},
+				Usage:   "get summary of directories fastly (NOTE: it may be inaccurate)",
+			},
 			&cli.BoolFlag{
 				Name:  "raw",
 				Usage: "show internal raw information",
@@ -73,10 +78,13 @@ func info(ctx *cli.Context) error {
 		logger.Infof("Windows is not supported")
 		return nil
 	}
-	var recursive, raw uint8
+	var recursive, fast, raw uint8
 	if ctx.Bool("recursive") {
 		recursive = 1
 	}
+	if ctx.Bool("fast") {
+		fast = 1
+	}
 	if ctx.Bool("raw") {
 		raw = 1
 	}
@@ -108,11 +116,12 @@ func info(ctx *cli.Context) error {
 			continue
 		}
 
-		wb := utils.NewBuffer(8 + 10)
+		wb := utils.NewBuffer(8 + 11)
 		wb.Put32(meta.InfoV2)
-		wb.Put32(10)
+		wb.Put32(11)
 		wb.Put64(inode)
 		wb.Put8(recursive)
+		wb.Put8(fast)
 		wb.Put8(raw)
 		_, err = f.Write(wb.Bytes())
 		if err != nil {

pkg/meta/utils.go

@@ -369,3 +369,50 @@ func GetSummary(r Meta, ctx Context, inode Ino, summary *Summary, recursive bool
 	}
 	return 0
 }
+
+func FastGetSummary(r Meta, ctx Context, inode Ino, summary *Summary, recursive bool) syscall.Errno {
+	var attr Attr
+	if st := r.GetAttr(ctx, inode, &attr); st != 0 {
+		return st
+	}
+	if attr.Typ == TypeDirectory {
+		return fastGetSummary(r, ctx, inode, summary, recursive)
+	} else {
+		summary.Files++
+		summary.Length += attr.Length
+		summary.Size += uint64(align4K(attr.Length))
+	}
+	return 0
+}
+
+func fastGetSummary(r Meta, ctx Context, inode Ino, summary *Summary, recursive bool) syscall.Errno {
+	space, _, err := r.GetDirStat(ctx, inode)
+	if err != nil {
+		return errno(err)
+	}
+	summary.Size += space
+	summary.Length += space
+	summary.Dirs++
+
+	var entries []*Entry
+	if st := r.Readdir(ctx, inode, 0, &entries); st != 0 {
+		return st
+	}
+	for _, e := range entries {
+		if e.Inode == inode || len(e.Name) == 2 && bytes.Equal(e.Name, []byte("..")) {
+			continue
+		}
+		if e.Attr.Typ == TypeDirectory {
+			if recursive {
+				if st := fastGetSummary(r, ctx, e.Inode, summary, recursive); st != 0 {
+					return st
+				}
+			} else {
+				summary.Dirs++
+			}
+		} else {
+			summary.Files++
+		}
+	}
+	return 0
+}

pkg/vfs/internal.go

@@ -394,12 +394,21 @@ func (v *VFS) handleInternalMsg(ctx meta.Context, cmd uint32, r *utils.Buffer, o
 		if r.HasMore() {
 			recursive = r.Get8()
 		}
+		var fast uint8
+		if r.HasMore() {
+			fast = r.Get8()
+		}
 		var raw bool
 		if r.HasMore() {
 			raw = r.Get8() != 0
 		}
 
-		r := meta.GetSummary(v.Meta, ctx, inode, &info.Summary, recursive != 0)
+		var r syscall.Errno
+		if fast == 0 {
+			r = meta.GetSummary(v.Meta, ctx, inode, &info.Summary, recursive != 0)
+		} else {
+			r = meta.FastGetSummary(v.Meta, ctx, inode, &info.Summary, recursive != 0)
+		}
 		if r != 0 {
 			info.Failed = true
 			info.Reason = r.Error()