当尝试在 Spark 的 MLLib 中使用 ALS 训练机器学习模型时,我不断收到 StackoverflowError。这是堆栈跟踪的一个小样本:
Traceback (most recent call last):
File "/Users/user/Spark/imf.py", line 31, in <module>
model = ALS.train(rdd, rank, numIterations)
File "/usr/local/Cellar/apache-spark/1.3.1_1/libexec/python/pyspark/mllib/recommendation.py", line 140, in train
lambda_, blocks, nonnegative, seed)
File "/usr/local/Cellar/apache-spark/1.3.1_1/libexec/python/pyspark/mllib/common.py", line 120, in callMLlibFunc
return callJavaFunc(sc, api, *args)
File "/usr/local/Cellar/apache-spark/1.3.1_1/libexec/python/pyspark/mllib/common.py", line 113, in callJavaFunc
return _java2py(sc, func(*args))
File "/usr/local/Cellar/apache-spark/1.3.1_1/libexec/python/lib/py4j-0.8.2.1-src.zip/py4j/java_gateway.py", line 538, in __call__
File "/usr/local/Cellar/apache-spark/1.3.1_1/libexec/python/lib/py4j-0.8.2.1-src.zip/py4j/protocol.py", line 300, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o35.trainALSModel.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 40.0 failed 1 times, most recent failure: Lost task 0.0 in stage 40.0 (TID 35, localhost): java.lang.StackOverflowError
at java.io.ObjectInputStream$PeekInputStream.peek(ObjectInputStream.java:2296)
at java.io.ObjectInputStream$BlockDataInputStream.peek(ObjectInputStream.java:2589)
当尝试运行 .mean() 来计算均方误差时,也会出现此错误。它出现在Spark的1.3.1_1版本和1.4.1版本中。我正在使用 PySpark,增加可用内存并没有帮助。