diff --git a/container/raw/container_hints.go b/container/raw/container_hints.go
index e63d1441..64d72f84 100644
--- a/container/raw/container_hints.go
+++ b/container/raw/container_hints.go
@@ -38,8 +38,8 @@ type containerHint struct {
 }
 
 type mount struct {
-	HostDir string `json:"host-dir,omitempty"`
-	ContainerDir string `json:"container-dir,omitempty"`
+	HostDir string `json:"host_dir,omitempty"`
+	ContainerDir string `json:"container_dir,omitempty"`
 }
 
 type networkInterface struct {
diff --git a/container/raw/handler.go b/container/raw/handler.go
index c8eee8e8..12f00e0b 100644
--- a/container/raw/handler.go
+++ b/container/raw/handler.go
@@ -190,11 +190,11 @@ func (self *rawContainerHandler) getFsStats(stats *info.ContainerStats) error {
 		for _, fs := range filesystems {
 			stats.Filesystem = append(stats.Filesystem, info.FsStats{fs.Device, fs.Capacity, fs.Capacity - fs.Free})
 		}
-	} else if self.mounts != nil {
-		var mountSet map[string]bool
-		mountSet = make(map[string]bool)
+	} else if len(self.mounts) > 0 {
+		var mountSet map[string]struct{}
+		mountSet = make(map[string]struct{})
 		for _, mount := range self.mounts {
-			mountSet[mount.HostDir] = true
+			mountSet[mount.HostDir] = struct{}{}
 		}
 		filesystems, err := self.fsInfo.GetFsInfoForPath(mountSet)
 		if err != nil {
diff --git a/container/raw/test_resources/container_hints.json b/container/raw/test_resources/container_hints.json
index d6d95fb8..d8842e55 100644
--- a/container/raw/test_resources/container_hints.json
+++ b/container/raw/test_resources/container_hints.json
@@ -9,28 +9,28 @@
       },
       "mounts": [
         {
-          "host-dir": "/var/run/nm-sdc1",
-          "container-dir": "/var/run/nm-sdc1",
+          "host_dir": "/var/run/nm-sdc1",
+          "container_dir": "/var/run/nm-sdc1",
           "permission": "rw"
         },
         {
-          "host-dir": "/var/run/nm-sdb3",
-          "container-dir": "/var/run/nm-sdb3",
+          "host_dir": "/var/run/nm-sdb3",
+          "container_dir": "/var/run/nm-sdb3",
           "permission": "rw"
         },
         {
-          "host-dir": "/var/run/nm-sda3",
-          "container-dir": "/var/run/nm-sda3",
+          "host_dir": "/var/run/nm-sda3",
+          "container_dir": "/var/run/nm-sda3",
           "permission": "rw"
         },
         {
-          "host-dir": "/var/run/netns/root",
-          "container-dir": "/var/run/netns/root",
+          "host_dir": "/var/run/netns/root",
+          "container_dir": "/var/run/netns/root",
           "permission": "ro"
         },
         {
-          "host-dir": "/var/run/openvswitch/db.sock",
-          "container-dir": "/var/run/openvswitch/db.sock",
+          "host_dir": "/var/run/openvswitch/db.sock",
+          "container_dir": "/var/run/openvswitch/db.sock",
           "permission": "rw"
         }
       ],
diff --git a/fs/fs.go b/fs/fs.go
index b1830ba9..db492ff6 100644
--- a/fs/fs.go
+++ b/fs/fs.go
@@ -50,16 +50,18 @@ func NewFsInfo() (FsInfo, error) {
 	return &RealFsInfo{partitions}, nil
 }
 
-func (self *RealFsInfo) GetFsInfoForPath(mountSet map[string]bool) ([]Fs, error) {
+func (self *RealFsInfo) GetFsInfoForPath(mountSet map[string]struct{}) ([]Fs, error) {
 	filesystems := make([]Fs, 0)
-	deviceSet := make(map[string]bool)
+	deviceSet := make(map[string]struct{})
 	for device, partition := range self.partitions {
-		if mountSet == nil || mountSet[partition.mountpoint] == true {
+		_, hasMount := mountSet[partition.mountpoint]
+		_, hasDevice := deviceSet[device]
+		if mountSet == nil ||  hasMount && !hasDevice {
 			total, free, err := getVfsStats(partition.mountpoint)
 			if err != nil {
 				glog.Errorf("Statvfs failed. Error: %v", err)
-			} else if deviceSet[device] == false {
-				deviceSet[device] = true
+			} else {
+				deviceSet[device] = struct{}{}
 				deviceInfo := DeviceInfo{
 					Device: device,
 					Major:  uint(partition.major),
diff --git a/fs/types.go b/fs/types.go
index c27fe99a..3d54ecb6 100644
--- a/fs/types.go
+++ b/fs/types.go
@@ -17,7 +17,7 @@ type FsInfo interface {
 	GetGlobalFsInfo() ([]Fs, error)
 
 	// Returns capacity and free space, in bytes, of the set of mounts passed.
-	GetFsInfoForPath(mountSet map[string]bool) ([]Fs, error)
+	GetFsInfoForPath(mountSet map[string]struct{}) ([]Fs, error)
 
 	// Returns number of bytes occupied by 'dir'.
 	GetDirUsage(dir string) (uint64, error)