Add image layer storage usage (#8430)

The current implementation of image storage usage always use
vCenter datastore file browser to get all layers of images
and sum the related vmdk file sizes. In some vsphere environments,
the browser response is very slow with 30+ seconds with
only 10 layers.

This fix changes to accumulate storage usage when a layer is added
or deleted from datastore, and keep the latest usage value into cache.

lib/apiservers/portlayer/restapi/handlers/storage_handlers.go

@@ -738,13 +738,19 @@ func (h *StorageHandlersImpl) GetImageStorageUsage(params storage.GetImageStorag
 	op := trace.NewOperationFromID(context.Background(), params.OpID, "GetImageStorageUsage(%s)", params.StoreName)
 	defer trace.End(trace.Begin("GetImageStorageUsage", op))
 
-	result, err := h.imageCache.DataStore.GetImageStorageUsage(op, params.StoreName)
-	if err != nil {
-		op.Errorf("Error gettting image storage usage: %s", err)
-		return storage.NewGetImageStorageUsageDefault(500)
+	cachedResult := h.imageCache.ImageStorageUsage()
+	// If cache is not set, read it from datastore
+	if cachedResult < 0 {
+		result, err := h.imageCache.DataStore.GetImageStorageUsage(op, params.StoreName)
+		if err != nil {
+			op.Errorf("Error getting image storage usage from datastore: %s", err)
+			return storage.NewGetImageStorageUsageDefault(500)
+		}
+		h.imageCache.SetImageStorageUsage(result)
+		cachedResult = result
 	}
 
-	return storage.NewGetImageStorageUsageOK().WithPayload(result)
+	return storage.NewGetImageStorageUsageOK().WithPayload(cachedResult)
 }
 
 //utility functions

lib/portlayer/storage/image/cache/cache.go

@@ -50,12 +50,16 @@ type NameLookupCache struct {
 
 	// The image store implementation.  This mutates the actual disk images.
 	DataStore image.ImageStorer
+
+	// Track image layers storage usage
+	imageStorageUsage int64
 }
 
 func NewLookupCache(ds image.ImageStorer) *NameLookupCache {
 	return &NameLookupCache{
-		DataStore:  ds,
-		storeCache: make(map[url.URL]*index.Index),
+		DataStore:         ds,
+		storeCache:        make(map[url.URL]*index.Index),
+		imageStorageUsage: -1,
 	}
 }
 
@@ -265,6 +269,10 @@ func (c *NameLookupCache) WriteImage(op trace.Operation, parent *image.Image, ID
 		return nil, err
 	}
 
+	if err = c.UpdateStorageUsage(op, i.Store, i.ID); err != nil {
+		return nil, err
+	}
+
 	c.storeCacheLock.Lock()
 	indx := c.storeCache[*parent.Store]
 	c.storeCacheLock.Unlock()
@@ -277,6 +285,25 @@ func (c *NameLookupCache) WriteImage(op trace.Operation, parent *image.Image, ID
 	return i, nil
 }
 
+func (c *NameLookupCache) UpdateStorageUsage(op trace.Operation, store *url.URL, id string) error {
+	storeName, err := util.ImageStoreName(store)
+	if err != nil {
+		return err
+	}
+	size, err := c.DataStore.GetImageLayerStorageUsage(op, storeName, id)
+	if err != nil {
+		op.Errorf("Get image layer size of %s failed with: %s", id, err)
+		// size is 0 and continue
+	}
+
+	if size > 0 {
+		c.storeCacheLock.Lock()
+		c.imageStorageUsage += size
+		c.storeCacheLock.Unlock()
+	}
+	return nil
+}
+
 func (c *NameLookupCache) Export(op trace.Operation, store *url.URL, id, ancestor string, spec *archive.FilterSpec, data bool) (io.ReadCloser, error) {
 	return c.DataStore.Export(op, id, ancestor, spec, data)
 }
@@ -424,12 +451,31 @@ func (c *NameLookupCache) DeleteImage(op trace.Operation, img *image.Image) (*im
 		return nil, &image.ErrImageInUse{Msg: img.Self() + " in use by child images"}
 	}
 
+	// Get image layer storage usage
+	storeName, err := util.ImageStoreName(img.Store)
+	if err != nil {
+		return nil, err
+	}
+
+	size, err := c.DataStore.GetImageLayerStorageUsage(op, storeName, img.ID)
+	if err != nil {
+		op.Errorf("Get image layer size of %s failed with: %s", img.ID, err)
+		// size is 0 and continue
+	}
+
 	// The datastore will tell us if the image is attached
 	if _, err = c.DataStore.DeleteImage(op, img); err != nil {
 		op.Errorf("%s", err)
 		return nil, err
 	}
 
+	// update image storage usage
+	if size > 0 {
+		c.storeCacheLock.Lock()
+		c.imageStorageUsage -= size
+		c.storeCacheLock.Unlock()
+	}
+
 	// Remove the image from the cache
 	if _, err = indx.Delete(img.Self()); err != nil {
 		op.Errorf("%s", err)
@@ -507,3 +553,15 @@ func (c *NameLookupCache) DeleteBranch(op trace.Operation, img *image.Image, kee
 
 	return deletedImages, nil
 }
+
+func (c *NameLookupCache) ImageStorageUsage() int64 {
+	c.storeCacheLock.Lock()
+	defer c.storeCacheLock.Unlock()
+	return c.imageStorageUsage
+}
+
+func (c *NameLookupCache) SetImageStorageUsage(value int64) {
+	c.storeCacheLock.Lock()
+	defer c.storeCacheLock.Unlock()
+	c.imageStorageUsage = value
+}

lib/portlayer/storage/image/image.go

@@ -79,6 +79,9 @@ type ImageStorer interface {
 	// GetImageStorageUsage gets the image storage usage from the image store.
 	GetImageStorageUsage(op trace.Operation, storeName string) (int64, error)
 
+	// GetImageLayerStorageUsage gets the image layer storage usage from the image store.
+	GetImageLayerStorageUsage(op trace.Operation, storeName, ID string) (int64, error)
+
 	storage.Resolver
 	storage.Importer
 	storage.Exporter

lib/portlayer/storage/image/mock/store.go

@@ -190,3 +190,7 @@ func (c *MockDataStore) DeleteImage(op trace.Operation, image *image.Image) (*im
 func (c *MockDataStore) GetImageStorageUsage(op trace.Operation, storeName string) (int64, error) {
 	return 0, nil
 }
+
+func (c *MockDataStore) GetImageLayerStorageUsage(op trace.Operation, storeName, ID string) (int64, error) {
+	return 0, nil
+}

lib/portlayer/storage/image/vsphere/store.go

@@ -122,7 +122,7 @@ func (v *ImageStore) imageStorePath(storeName string) string {
 
 // Returns the path to the image relative to the given
 // store.  The dir structure for an image in the datastore is
-// `/VIC/imageStoreName (currently the vch uuid)/imageName/imageName.vmkd`
+// `/VIC/imageStoreName (currently the vch uuid)/imageName/imageName.vmdk`
 func (v *ImageStore) imageDirPath(storeName, imageName string) string {
 	return path.Join(v.imageStorePath(storeName), imageName)
 }
@@ -594,6 +594,10 @@ func (v *ImageStore) GetImageStorageUsage(op trace.Operation, storeName string)
 	return v.Helper.GetFilesSize(op, v.imageStorePath(storeName), true, "*.vmdk")
 }
 
+func (v *ImageStore) GetImageLayerStorageUsage(op trace.Operation, storeName, ID string) (int64, error) {
+	return v.Helper.GetFilesSize(op, v.imageDirPath(storeName, ID), true, "*.vmdk")
+}
+
 // DeleteImage deletes an image from the image store.  If the image is in
 // use either by way of inheritance or because it's attached to a
 // container, this will return an error.