hadoop - Spark - Snappy 库不可用

Question

我正在尝试保存 Mllib 模型。

我在 Spark 中运行的代码:

model = RandomForest.trainClassifier(train_data, 
                                 numClasses=2, categoricalFeaturesInfo=categoricalFeaturesInfo,
                                 numTrees=numTrees, featureSubsetStrategy="auto",
                                 impurity=impurity, maxDepth=maxDepth, maxBins=maxBins)

model.save(sc, "file:///path/to/models/model_name")

错误信息是:

native snappy library not available: 
this version of libhadoop was built without snappy support

Spark的资料

星火版本:

1.6.1

启动Spark的代码:

pyspark --packages com.databricks:spark-csv_2.11:1.5.0 --master "local[8]" --driver-memory 6G --executor-memory 6G --jars /usr/local/path/to/hadoop/lib/snappy-java-1.0.4.1.jar

环境变量(spark_env.sh):

HADOOP_HOME=/usr/local/path/to/hadoop 
SPARK_HOME=/usr/local/path/to/spark
HADOOP_CONF_DIR=/usr/local/path/to/hadoop/etc/hadoop
SPARK_CONF_DIR=/usr/local/path/to/spark/conf
HADOOP_LZO_DIR=/usr/local/path/to/hadoop/lib
HADOOP_CLASSPATH=$HADOOP_CLASSPATH:/usr/local/path/to/spark/*:/usr/local/path/to/spark/lib/*:/usr/local/path/to/hadoop/lib/*:/usr/local/path/to/hadoop/lib/native/*
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/path/to/hadoop/lib/native
SPARK_CLASSPATH=$SPARK_CLASSPATH:/usr/local/path/to/hadoop/lib/native/*:/usr/local/path/to/hadoop/lib/snappy-java-1.0.4.1.jar:/usr.local/path/to/spark/lib/*:$CLASSPATH

我故意在 SPARK_CLASSPATH 中添加了 /usr/local/path/to/hadoop/lib/snappy-java-1.0.4.1.jar 但没有用。

Answer 1

接下来的步骤帮助我解决了类似的问题:

从 https://hadoop.apache.org/releases.html 下载 hadoop 库,在本地解压并将 spark.driver.extraLibraryPath 设置为 $HADOOP_PATH/lib/native。

例子:

pyspark --packages com.databricks:spark-csv_2.11:1.5.0 --master "local[8]"--conf "spark.driver.extraLibraryPath=/home/hadoop/hadoop-2.8 .1/lib/native"--driver-memory 6G --executor-memory 6G --jars/usr/local/path/to/hadoop/lib/snappy-java-1.0.4.1.jar/p>

如果对您不起作用，您可以尝试将 spark.executor.extraLibraryPath 设置为相同的值。