shows total memory usage

cursor.go

@@ -17,6 +17,16 @@ type GridCursor struct {
 
 func (gc *GridCursor) Len() int { return len(gc.filtered) }
 
+func (gc *GridCursor) MemoryUsage() int64 {
+	var size int64
+	size = 0
+	for _, c := range gc.filtered {
+		size += c.MemUsage
+	}
+	gc.Reset()
+	return size
+}
+
 func (gc *GridCursor) Selected() *container.Container {
 	idx := gc.Idx()
 	if idx < gc.Len() {

grid.go

@@ -52,6 +52,7 @@ func RedrawRows(clr bool) {
 	y := 1
 	if config.GetSwitchVal("enableHeader") {
 		header.SetCount(cursor.Len())
+		header.SetMemoryUsage(cursor.MemoryUsage())
 		header.SetFilter(config.GetVal("filterStr"))
 		y += header.Height()
 	}

widgets/header.go

@@ -3,7 +3,7 @@ package widgets
 import (
 	"fmt"
 	"time"
-
+	"github.com/bcicen/ctop/cwidgets"
 	ui "github.com/gizak/termui"
 )
 
@@ -11,6 +11,7 @@ type CTopHeader struct {
 	Time   *ui.Par
 	Count  *ui.Par
 	Filter *ui.Par
+	Mem    *ui.Par
 	bg     *ui.Par
 }
 
@@ -19,6 +20,7 @@ func NewCTopHeader() *CTopHeader {
 		Time:   headerPar(2, ""),
 		Count:  headerPar(24, "-"),
 		Filter: headerPar(40, ""),
+		Mem:    headerPar(70, ""),
 		bg:     headerBg(),
 	}
 }
@@ -30,6 +32,7 @@ func (c *CTopHeader) Buffer() ui.Buffer {
 	buf.Merge(c.Time.Buffer())
 	buf.Merge(c.Count.Buffer())
 	buf.Merge(c.Filter.Buffer())
+	buf.Merge(c.Mem.Buffer())
 	return buf
 }
 
@@ -58,6 +61,10 @@ func headerBg() *ui.Par {
 	return bg
 }
 
+func (c *CTopHeader) SetMemoryUsage(val int64) {
+	c.Mem.Text = cwidgets.ByteFormat(val)
+}
+
 func (c *CTopHeader) SetCount(val int) {
 	c.Count.Text = fmt.Sprintf("%d containers", val)
 }