java - 使用有限堆的 azure-sdk-for-java 上传大文件

Question

我们正在开发文档微服务，需要使用Azure作为文件内容的存储。 Azure Block Blob 似乎是一个合理的选择。文档服务的堆限制为 512MB ( -Xmx512m )。

我没有成功使用 azure-storage-blob:12.10.0-beta.1 使用有限的堆进行流式文件上传。 (也在 12.9.0 上进行了测试)。

尝试了以下方法:

1. 从 documentation 复制粘贴使用BlockBlobClient

BlockBlobClient blockBlobClient = blobContainerClient.getBlobClient("file").getBlockBlobClient();

File file = new File("file");

try (InputStream dataStream = new FileInputStream(file)) {
  blockBlobClient.upload(dataStream, file.length(), true /* overwrite file */);
}

结果: java.io.IOException: mark/reset not supported - SDK 尝试使用标记/重置，即使文件输入流报告不支持此功能。

添加BufferedInputStream缓解标记/重置问题(根据 advice ):

BlockBlobClient blockBlobClient = blobContainerClient.getBlobClient("file").getBlockBlobClient();

File file = new File("file");

try (InputStream dataStream = new BufferedInputStream(new FileInputStream(file))) {
  blockBlobClient.upload(dataStream, file.length(), true /* overwrite file */);
}

结果: java.lang.OutOfMemoryError: Java heap space 。我假设 SDK 尝试将所有 1.17GB 的文件内容加载到内存中。

替换 BlockBlobClient与 BlobClient并删除堆大小限制( -Xmx512m ):

BlobClient blobClient = blobContainerClient.getBlobClient("file");

File file = new File("file");

try (InputStream dataStream = new FileInputStream(file)) {
  blobClient.upload(dataStream, file.length(), true /* overwrite file */);
}

结果:使用了 1.5GB 堆内存，所有文件内容都加载到内存中 + Reactor 侧进行一些缓冲

Heap usage from VisualVM

通过 BlobOutputStream 切换到流式传输:

long blockSize = DataSize.ofMegabytes(4L).toBytes();

BlockBlobClient blockBlobClient = blobContainerClient.getBlobClient("file").getBlockBlobClient();

// create / erase blob
blockBlobClient.commitBlockList(List.of(), true);

BlockBlobOutputStreamOptions options = (new BlockBlobOutputStreamOptions()).setParallelTransferOptions(
  (new ParallelTransferOptions()).setBlockSizeLong(blockSize).setMaxConcurrency(1).setMaxSingleUploadSizeLong(blockSize));

try (InputStream is = new FileInputStream("file")) {
  try (OutputStream os = blockBlobClient.getBlobOutputStream(options)) {
    IOUtils.copy(is, os); // uses 8KB buffer
  }
}

结果:文件在上传过程中损坏。 Azure Web 门户显示 1.09GB，而不是预期的 1.17GB。从 Azure Web 门户手动下载文件确认文件内容在上传过程中已损坏。内存占用显着减少，但文件损坏却是一个大问题。

问题:无法提供内存占用较小的有效上传/下载解决方案

任何帮助将不胜感激!

Answer 1

请尝试使用下面的代码来上传/下载大文件，我已经使用大小约为 1.1 GB 的 .zip 文件进行了测试

上传文件:

public static void uploadFilesByChunk() {
                String connString = "<conn str>";
                String containerName = "<container name>";
                String blobName = "UploadOne.zip";
                String filePath = "D:/temp/" + blobName;

                BlobServiceClient client = new BlobServiceClientBuilder().connectionString(connString).buildClient();
                BlobClient blobClient = client.getBlobContainerClient(containerName).getBlobClient(blobName);
                long blockSize = 2 * 1024 * 1024; //2MB
                ParallelTransferOptions parallelTransferOptions = new ParallelTransferOptions()
                                .setBlockSizeLong(blockSize).setMaxConcurrency(2)
                                .setProgressReceiver(new ProgressReceiver() {
                                        @Override
                                        public void reportProgress(long bytesTransferred) {
                                                System.out.println("uploaded:" + bytesTransferred);
                                        }
                                });

                BlobHttpHeaders headers = new BlobHttpHeaders().setContentLanguage("en-US").setContentType("binary");

                blobClient.uploadFromFile(filePath, parallelTransferOptions, headers, null, AccessTier.HOT,
                                new BlobRequestConditions(), Duration.ofMinutes(30));
        }

内存占用:

下载文件:

public static void downLoadFilesByChunk() {
                String connString = "<conn str>";
                String containerName = "<container name>";
                String blobName = "UploadOne.zip";

                String filePath = "D:/temp/" + "DownloadOne.zip";

                BlobServiceClient client = new BlobServiceClientBuilder().connectionString(connString).buildClient();
                BlobClient blobClient = client.getBlobContainerClient(containerName).getBlobClient(blobName);
                long blockSize = 2 * 1024 * 1024;
                com.azure.storage.common.ParallelTransferOptions parallelTransferOptions = new com.azure.storage.common.ParallelTransferOptions()
                                .setBlockSizeLong(blockSize).setMaxConcurrency(2)
                                .setProgressReceiver(new com.azure.storage.common.ProgressReceiver() {
                                        @Override
                                        public void reportProgress(long bytesTransferred) {
                                                System.out.println("dowloaded:" + bytesTransferred);
                                        }
                                });

                BlobDownloadToFileOptions options = new BlobDownloadToFileOptions(filePath)
                                .setParallelTransferOptions(parallelTransferOptions);
                blobClient.downloadToFileWithResponse(options, Duration.ofMinutes(30), null);
        }

内存占用:

结果: