[s3 cache] Faster download with parallelism

cache/remotecache/s3/s3.go

@@ -34,36 +34,40 @@ import (
 )
 
 const (
-	attrBucket            = "bucket"
-	attrRegion            = "region"
-	attrPrefix            = "prefix"
-	attrManifestsPrefix   = "manifests_prefix"
-	attrBlobsPrefix       = "blobs_prefix"
-	attrName              = "name"
-	attrTouchRefresh      = "touch_refresh"
-	attrEndpointURL       = "endpoint_url"
-	attrAccessKeyID       = "access_key_id"
-	attrSecretAccessKey   = "secret_access_key"
-	attrSessionToken      = "session_token"
-	attrUsePathStyle      = "use_path_style"
-	attrUploadParallelism = "upload_parallelism"
-	maxCopyObjectSize     = 5 * 1024 * 1024 * 1024
+	attrBucket              = "bucket"
+	attrRegion              = "region"
+	attrPrefix              = "prefix"
+	attrManifestsPrefix     = "manifests_prefix"
+	attrBlobsPrefix         = "blobs_prefix"
+	attrName                = "name"
+	attrTouchRefresh        = "touch_refresh"
+	attrEndpointURL         = "endpoint_url"
+	attrAccessKeyID         = "access_key_id"
+	attrSecretAccessKey     = "secret_access_key"
+	attrSessionToken        = "session_token"
+	attrUsePathStyle        = "use_path_style"
+	attrUploadParallelism   = "upload_parallelism"
+	attrDownloadParallelism = "download_parallelism"
+	attrDownloadPartSize    = "download_part_size"
+	maxCopyObjectSize       = 5 * 1024 * 1024 * 1024
 )
 
 type Config struct {
-	Bucket            string
-	Region            string
-	Prefix            string
-	ManifestsPrefix   string
-	BlobsPrefix       string
-	Names             []string
-	TouchRefresh      time.Duration
-	EndpointURL       string
-	AccessKeyID       string
-	SecretAccessKey   string
-	SessionToken      string
-	UsePathStyle      bool
-	UploadParallelism int
+	Bucket              string
+	Region              string
+	Prefix              string
+	ManifestsPrefix     string
+	BlobsPrefix         string
+	Names               []string
+	TouchRefresh        time.Duration
+	EndpointURL         string
+	AccessKeyID         string
+	SecretAccessKey     string
+	SessionToken        string
+	UsePathStyle        bool
+	UploadParallelism   int
+	DownloadParallelism int
+	DownloadPartSize    int
 }
 
 func getConfig(attrs map[string]string) (Config, error) {
@@ -141,20 +145,48 @@ func getConfig(attrs map[string]string) (Config, error) {
 		uploadParallelism = uploadParallelismInt
 	}
 
+	downloadParallism := 4
+	downloadParallismStr, ok := attrs[attrDownloadParallelism]
+	if ok {
+		downloadParallismInt, err := strconv.Atoi(downloadParallismStr)
+		if err != nil {
+			return Config{}, errors.Errorf("download_parallelism must be a positive integer")
+		}
+		if downloadParallismInt <= 0 {
+			return Config{}, errors.Errorf("download_parallelism must be a positive integer")
+		}
+		downloadParallism = downloadParallismInt
+	}
+
+	downloadPartSize := 5 * 1024 * 1024
+	downloadPartSizeStr, ok := attrs[attrDownloadPartSize]
+	if ok {
+		downloadPartSizeInt, err := strconv.Atoi(downloadPartSizeStr)
+		if err != nil {
+			return Config{}, errors.Errorf("download_part_size must be a positive integer")
+		}
+		if downloadPartSizeInt <= 0 {
+			return Config{}, errors.Errorf("download_part_size must be a positive integer")
+		}
+		downloadParallism = downloadPartSizeInt
+	}
+
 	return Config{
-		Bucket:            bucket,
-		Region:            region,
-		Prefix:            prefix,
-		ManifestsPrefix:   manifestsPrefix,
-		BlobsPrefix:       blobsPrefix,
-		Names:             names,
-		TouchRefresh:      touchRefresh,
-		EndpointURL:       endpointURL,
-		AccessKeyID:       accessKeyID,
-		SecretAccessKey:   secretAccessKey,
-		SessionToken:      sessionToken,
-		UsePathStyle:      usePathStyle,
-		UploadParallelism: uploadParallelism,
+		Bucket:              bucket,
+		Region:              region,
+		Prefix:              prefix,
+		ManifestsPrefix:     manifestsPrefix,
+		BlobsPrefix:         blobsPrefix,
+		Names:               names,
+		TouchRefresh:        touchRefresh,
+		EndpointURL:         endpointURL,
+		AccessKeyID:         accessKeyID,
+		SecretAccessKey:     secretAccessKey,
+		SessionToken:        sessionToken,
+		UsePathStyle:        usePathStyle,
+		UploadParallelism:   uploadParallelism,
+		DownloadParallelism: downloadParallism,
+		DownloadPartSize:    downloadPartSize,
 	}, nil
 }
 
@@ -385,22 +417,15 @@ func (i *importer) Resolve(ctx context.Context, _ ocispecs.Descriptor, id string
 	return solver.NewCacheManager(ctx, id, keysStorage, resultStorage), nil
 }
 
-type readerAt struct {
-	ReaderAtCloser
-	size int64
-}
-
-func (r *readerAt) Size() int64 {
-	return r.size
-}
-
 type s3Client struct {
 	*s3.Client
 	*manager.Uploader
-	bucket          string
-	prefix          string
-	blobsPrefix     string
-	manifestsPrefix string
+	bucket              string
+	prefix              string
+	blobsPrefix         string
+	manifestsPrefix     string
+	downloadParallelism int
+	downloadPartSize    int
 }
 
 func newS3Client(ctx context.Context, config Config) (*s3Client, error) {
@@ -419,12 +444,14 @@ func newS3Client(ctx context.Context, config Config) (*s3Client, error) {
 	})
 
 	return &s3Client{
-		Client:          client,
-		Uploader:        manager.NewUploader(client),
-		bucket:          config.Bucket,
-		prefix:          config.Prefix,
-		blobsPrefix:     config.BlobsPrefix,
-		manifestsPrefix: config.ManifestsPrefix,
+		Client:              client,
+		Uploader:            manager.NewUploader(client),
+		bucket:              config.Bucket,
+		prefix:              config.Prefix,
+		blobsPrefix:         config.BlobsPrefix,
+		manifestsPrefix:     config.ManifestsPrefix,
+		downloadParallelism: config.DownloadParallelism,
+		downloadPartSize:    config.DownloadPartSize,
 	}, nil
 }
 
@@ -454,19 +481,6 @@ func (s3Client *s3Client) getManifest(ctx context.Context, key string, config *v
 	return true, nil
 }
 
-func (s3Client *s3Client) getReader(ctx context.Context, key string) (io.ReadCloser, error) {
-	input := &s3.GetObjectInput{
-		Bucket: &s3Client.bucket,
-		Key:    &key,
-	}
-
-	output, err := s3Client.GetObject(ctx, input)
-	if err != nil {
-		return nil, err
-	}
-	return output.Body, nil
-}
-
 func (s3Client *s3Client) saveMutableAt(ctx context.Context, key string, body io.Reader) error {
 	input := &s3.PutObjectInput{
 		Bucket: &s3Client.bucket,
@@ -587,10 +601,18 @@ func (s3Client *s3Client) touch(ctx context.Context, key string, size *int64) (e
 }
 
 func (s3Client *s3Client) ReaderAt(ctx context.Context, desc ocispecs.Descriptor) (content.ReaderAt, error) {
-	readerAtCloser := toReaderAtCloser(func(offset int64) (io.ReadCloser, error) {
-		return s3Client.getReader(ctx, s3Client.blobKey(desc.Digest))
-	})
-	return &readerAt{ReaderAtCloser: readerAtCloser, size: desc.Size}, nil
+	key := s3Client.blobKey(desc.Digest)
+	input := &s3DownloaderInput{
+		Bucket:      &s3Client.bucket,
+		Key:         &key,
+		S3Client:    s3Client.Client,
+		Size:        desc.Size,
+		Parallelism: s3Client.downloadParallelism,
+		PartSize:    s3Client.downloadPartSize,
+	}
+	downloader := newDownloader(input)
+
+	return downloader.Download(ctx)
 }
 
 func (s3Client *s3Client) manifestKey(name string) string {