在Google Dataproc Spark中链接原生.so

Question

我有一个本地库(Freeling)，它是我使用cmake和make编译的，并通过集群启动操作安装(所以，它应该存在于master和每个worker中)。

即便如此，我在调用System.loadLibrary时还是收到了这个错误

Exception in thread "main" java.lang.UnsatisfiedLinkError: no Jfreeling in java.library.path
    at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1867)
    at java.lang.Runtime.loadLibrary0(Runtime.java:870)
    at java.lang.System.loadLibrary(System.java:1122)

我尝试使用以下属性让程序找到该库(在静态代码块中调用)

      "properties": {
        "spark.driver.extraClassPath": "/usr/local/share/freeling/APIs/java/Jfreeling.jar:/usr/local/lib/libfreeling.so",
        "spark.executor.extraClassPath": "/usr/local/share/freeling/APIs/java/Jfreeling.jar:/usr/local/lib/libfreeling.so",
        "spark.executor.extraLibraryPath": "/usr/local/lib/libfreeling.so",
        "spark.driver.extraLibraryPath": "/usr/local/lib/libfreeling.so",
        "spark.executorEnv.LD_PRELOAD": "/usr/local/lib/libfreeling.so",
        "spark.yarn.dist.files": "/usr/local/lib/libfreeling.so",
        "spark.yarn.appMasterEnv.LD_PRELOAD": "libfreeling.so",
        "spark.files": "/usr/local/lib/libfreeling.so",
        "spark.executorEnv.LD_LIBRARY_PATH": "libfreeling.so"
      },
      "jarFileUris": [
        "file:///usr/local/share/freeling/APIs/java/Jfreeling.jar",
        "file:///usr/local/lib/libfreeling.so"
      ],

Answer 1

你能试着把你的库放在/usr/lib/hadoop/lib/native/下吗？在/etc/spark/conf/spark-env.sh中，它有

# Spark got rid of SPARK_LIBRARY_PATH in 1.0
# It has properties for extraLibraryPaths, but this is more extensible
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:${HADOOP_HOME}/lib/native

Answer 2

您应该将/usr/local/share/freeling/APIs/java/Jfreeling.jar添加到您的类中，并将/usr/local/share/freeling/APIs/java/libJfreeling.so添加到您的LD_LIBRARY_PATH中。