@@ -111,6 +111,12 @@ type Daemon struct {

 	seccompProfile     []byte

 	seccompProfilePath string

+

+	diskUsageRunning       int32

+	containersPruneRunning int32

+	volumesPruneRunning    int32

+	imagesPruneRunning     int32

+	networksPruneRunning   int32

 }

 // HasExperimental returns whether the experimental features of the daemon are enabled or not

@@ -2,6 +2,7 @@ package daemon

 import (

 	"fmt"

+	"sync/atomic"

 	"golang.org/x/net/context"

@@ -37,6 +38,11 @@ func (daemon *Daemon) getLayerRefs() map[layer.ChainID]int {

 // SystemDiskUsage returns information about the daemon data disk usage

 func (daemon *Daemon) SystemDiskUsage(ctx context.Context) (*types.DiskUsage, error) {

+	if !atomic.CompareAndSwapInt32(&daemon.diskUsageRunning, 0, 1) {

+		return nil, fmt.Errorf("a disk usage operation is already running")

+	}

+	defer atomic.StoreInt32(&daemon.diskUsageRunning, 0)

+

 	// Retrieve container list

 	allContainers, err := daemon.Containers(&types.ContainerListOptions{

 		Size: true,