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Java HdfsConstants.IO_FILE_BUFFER_SIZE属性代码示例

本文整理汇总了Java中org.apache.hadoop.hdfs.protocol.HdfsConstants.IO_FILE_BUFFER_SIZE属性的典型用法代码示例。如果您正苦于以下问题:Java HdfsConstants.IO_FILE_BUFFER_SIZE属性的具体用法?Java HdfsConstants.IO_FILE_BUFFER_SIZE怎么用?Java HdfsConstants.IO_FILE_BUFFER_SIZE使用的例子?那么, 这里精选的属性代码示例或许可以为您提供帮助。您也可以进一步了解该属性所在org.apache.hadoop.hdfs.protocol.HdfsConstants的用法示例。


在下文中一共展示了HdfsConstants.IO_FILE_BUFFER_SIZE属性的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Java代码示例。

示例1: copyFileToStream

private static void copyFileToStream(OutputStream out, File localfile,
    FileInputStream infile, DataTransferThrottler throttler,
    Canceler canceler) throws IOException {
  byte buf[] = new byte[HdfsConstants.IO_FILE_BUFFER_SIZE];
  try {
    CheckpointFaultInjector.getInstance()
        .aboutToSendFile(localfile);

    if (CheckpointFaultInjector.getInstance().
          shouldSendShortFile(localfile)) {
        // Test sending image shorter than localfile
        long len = localfile.length();
        buf = new byte[(int)Math.min(len/2, HdfsConstants.IO_FILE_BUFFER_SIZE)];
        // This will read at most half of the image
        // and the rest of the image will be sent over the wire
        infile.read(buf);
    }
    int num = 1;
    while (num > 0) {
      if (canceler != null && canceler.isCancelled()) {
        throw new SaveNamespaceCancelledException(
          canceler.getCancellationReason());
      }
      num = infile.read(buf);
      if (num <= 0) {
        break;
      }
      if (CheckpointFaultInjector.getInstance()
            .shouldCorruptAByte(localfile)) {
        // Simulate a corrupted byte on the wire
        LOG.warn("SIMULATING A CORRUPT BYTE IN IMAGE TRANSFER!");
        buf[0]++;
      }
      
      out.write(buf, 0, num);
      if (throttler != null) {
        throttler.throttle(num, canceler);
      }
    }
  } catch (EofException e) {
    LOG.info("Connection closed by client");
    out = null; // so we don't close in the finally
  } finally {
    if (out != null) {
      out.close();
    }
  }
}
 
开发者ID:naver,项目名称:hadoop,代码行数:48,代码来源:TransferFsImage.java

示例2: blockChecksum

@Override
public void blockChecksum(final ExtendedBlock block,
    final Token<BlockTokenIdentifier> blockToken) throws IOException {
  final DataOutputStream out = new DataOutputStream(
      getOutputStream());
  checkAccess(out, true, block, blockToken,
      Op.BLOCK_CHECKSUM, BlockTokenSecretManager.AccessMode.READ);
  // client side now can specify a range of the block for checksum
  long requestLength = block.getNumBytes();
  Preconditions.checkArgument(requestLength >= 0);
  long visibleLength = datanode.data.getReplicaVisibleLength(block);
  boolean partialBlk = requestLength < visibleLength;

  updateCurrentThreadName("Reading metadata for block " + block);
  final LengthInputStream metadataIn = datanode.data
      .getMetaDataInputStream(block);
  
  final DataInputStream checksumIn = new DataInputStream(
      new BufferedInputStream(metadataIn, HdfsConstants.IO_FILE_BUFFER_SIZE));
  updateCurrentThreadName("Getting checksum for block " + block);
  try {
    //read metadata file
    final BlockMetadataHeader header = BlockMetadataHeader
        .readHeader(checksumIn);
    final DataChecksum checksum = header.getChecksum();
    final int csize = checksum.getChecksumSize();
    final int bytesPerCRC = checksum.getBytesPerChecksum();
    final long crcPerBlock = csize <= 0 ? 0 : 
      (metadataIn.getLength() - BlockMetadataHeader.getHeaderSize()) / csize;

    final MD5Hash md5 = partialBlk && crcPerBlock > 0 ? 
        calcPartialBlockChecksum(block, requestLength, checksum, checksumIn)
          : MD5Hash.digest(checksumIn);
    if (LOG.isDebugEnabled()) {
      LOG.debug("block=" + block + ", bytesPerCRC=" + bytesPerCRC
          + ", crcPerBlock=" + crcPerBlock + ", md5=" + md5);
    }

    //write reply
    BlockOpResponseProto.newBuilder()
      .setStatus(SUCCESS)
      .setChecksumResponse(OpBlockChecksumResponseProto.newBuilder()             
        .setBytesPerCrc(bytesPerCRC)
        .setCrcPerBlock(crcPerBlock)
        .setMd5(ByteString.copyFrom(md5.getDigest()))
        .setCrcType(PBHelper.convert(checksum.getChecksumType())))
      .build()
      .writeDelimitedTo(out);
    out.flush();
  } catch (IOException ioe) {
    LOG.info("blockChecksum " + block + " received exception " + ioe);
    incrDatanodeNetworkErrors();
    throw ioe;
  } finally {
    IOUtils.closeStream(out);
    IOUtils.closeStream(checksumIn);
    IOUtils.closeStream(metadataIn);
  }

  //update metrics
  datanode.metrics.addBlockChecksumOp(elapsed());
}
 
开发者ID:naver,项目名称:hadoop,代码行数:62,代码来源:DataXceiver.java


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