@@ -336,7 +336,7 @@ func (container *Container) GetSize() (int64, int64) {

 		sizeRw = -1

 	}

-	if _, err = os.Stat(container.basefs); err != nil {

+	if _, err = os.Stat(container.basefs); err == nil {

 		if sizeRootfs, err = directory.Size(container.basefs); err != nil {

 			sizeRootfs = -1

 		}

@@ -304,7 +304,7 @@ func (s *DockerSuite) TestPsListContainersSize(c *check.C) {

 	}

 	expectedSize := fmt.Sprintf("%d B", (2 + baseBytes))

 	foundSize := lines[1][sizeIndex:]

-	if foundSize != expectedSize {

+	if !strings.Contains(foundSize, expectedSize) {

 		c.Fatalf("Expected size %q, got %q", expectedSize, foundSize)

 	}

@@ -666,3 +666,17 @@ func (s *DockerSuite) TestPsGroupPortRange(c *check.C) {

 	}

 }

+

+func (s *DockerSuite) TestPsWithSize(c *check.C) {

+	out, _, err := runCommandWithOutput(exec.Command(dockerBinary, "run", "-d", "--name", "sizetest", "busybox", "top"))

+	if err != nil {

+		c.Fatal(out, err)

+	}

+	out, _, err = runCommandWithOutput(exec.Command(dockerBinary, "ps", "--size"))

+	if err != nil {

+		c.Fatal(out, err)

+	}

+	if !strings.Contains(out, "virtual") {

+		c.Fatalf("docker ps with --size should show virtual size of container")

+	}

+}