在 HDFS 上使用文件运行 tensorflow（找不到 libhdfs.so）

Question

我在尝试运行 python 脚本调用 Tensorflow 读取器对存储在 HDFS 中的文件时遇到错误“libhdfs.so：无法打开共享对象文件：没有这样的文件或目录”（下面的堆栈跟踪）。我正在集群上的一个节点上运行脚本，该节点在 virtualenv 中具有 Tensorflow，在执行时激活。我在执行前设置了以下环境变量：

• 导出 HADOOP_HDFS_HOME=$HADOOP_HDFS_HOME:/opt/cloudera/parcels/CDH
• 导出 JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
• 导出 LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/cloudera/parcels/CDH/lib/libhdfs.so
• 导出 LD_LIBRARY_PATH=$LD_LIBRARY_PATH:${JAVA_HOME}/jre/lib/amd64/server

我这样执行脚本：

• CLASSPATH=$($LD_LIBRARY_PATH} 类路径 --glob) python TEST.py

这是脚本中的代码：

filename_queue = tf.train.string_input_producer([   
   "hdfs://hostname:port/user/hdfs/test.avro" ]) 
reader =
   tf.WholeFileReader() key, value = reader.read(filename_queue)

   with tf.Session() as sess:
       coord = tf.train.Coordinator()
       threads = tf.train.start_queue_runners(coord=coord)
       sess.run([key,value])
       coord.request_stop()
       coord.join(threads)

下面是错误的堆栈跟踪。对导致此错误的原因的任何想法表示赞赏（我已经检查了 LD_LIBRARY_PATH 变量在执行之前是否具有指向 libhdfs.so 文件的显式指针，但无法弄清楚为什么它仍然找不到该文件）。

Traceback (most recent call last):
  File "TEST.py", line 25, in <module>
    sess.run([key,value])
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 767, in run
    run_metadata_ptr)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 965, in _run
    feed_dict_string, options, run_metadata)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1015, in _do_run
    target_list, options, run_metadata)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1035, in _do_call
    raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.NotFoundError: libhdfs.so: cannot open shared object file: No such file or directory
     [[Node: ReaderReadV2 = ReaderReadV2[_device="/job:localhost/replica:0/task:0/cpu:0"](WholeFileReaderV2, input_producer)]]

Caused by op u'ReaderReadV2', defined at:
  File "TEST.py", line 19, in <module>
    key, value = reader.read(filename_queue)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/ops/io_ops.py", line 272, in read
    return gen_io_ops._reader_read_v2(self._reader_ref, queue_ref, name=name)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/ops/gen_io_ops.py", line 410, in _reader_read_v2
    queue_handle=queue_handle, name=name)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/framework/op_def_library.py", line 763, in apply_op
    op_def=op_def)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2395, in create_op
    original_op=self._default_original_op, op_def=op_def)
  File "/home/username/tensorflow/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 1264, in __init__
    self._traceback = _extract_stack()

NotFoundError (see above for traceback): libhdfs.so: cannot open shared object file: No such file or directory

Answer 1

我也遇到了这个问题，我的解决方案是将这个文件复制到：

$HADOOP_HDFS_HOME/lib/native

如果您不知道该文件的位置，请执行以下命令来查找它的位置：

sudo updatedb
locate libhdfs.so

这将为您提供文件的位置。接下来将文件复制到 $HADOOP_HDFS_HOME/lib/native：

cp locationOflibhdfs.so $HADOOP_HDFS_HOME/lib/native

注意：将 locationOflibhdfs.so 替换为 libhdfs.so 文件的位置。