hadoop Job 运行错误 java.lang.OutOfMemoryError: Java heap space

错误详细内容如下：

2015-12-04 01:21:46,557 FATAL [netty-server-worker-1] org.apache.giraph.graph.GraphTaskManager: uncaughtException: OverrideExceptionHandler on thread netty-server-worker-1, msg = Java heap space,

exiting...

java.lang.OutOfMemoryError: Java heap space

at java.lang.Throwable.getStackTraceElement(Native Method)

at java.lang.Throwable.getOurStackTrace(Throwable.java:827)

at java.lang.Throwable.getStackTrace(Throwable.java:816)

at io.netty.channel.DefaultChannelHandlerContext.inExceptionCaught(DefaultChannelHandlerContext.java:750)

at io.netty.channel.DefaultChannelHandlerContext.notifyHandlerException(DefaultChannelHandlerContext.java:736)

at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:340)

at io.netty.channel.DefaultChannelHandlerContext.fireChannelRead(DefaultChannelHandlerContext.java:324)

at org.apache.giraph.comm.netty.handler.RequestDecoder.channelRead(RequestDecoder.java:100)

at io.netty.channel.DefaultChannelHandlerContext.invokeChannelRead(DefaultChannelHandlerContext.java:338)

at io.netty.channel.DefaultChannelHandlerContext.access$700(DefaultChannelHandlerContext.java:29)

at io.netty.channel.DefaultChannelHandlerContext$8.run(DefaultChannelHandlerContext.java:329)

at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:354)

at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:353)

at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:101)

at java.lang.Thread.run(Thread.java:745)

2015-12-04 01:21:47,210 ERROR [netty-server-worker-1] org.apache.giraph.worker.BspServiceWorker: unregisterHealth: Got failure, unregistering health on /_hadoopBsp/job_1449219833144_0001/_applicat

ionAttemptsDir/0/_superstepDir/-1/_workerHealthyDir/master_3 on superstep -1

错误原因：mapred-default.xml中mapred.child.java.opts=-Xmx200m太小了，导致内存溢出

解决方法：在mapred-site.xml中添加如下内容：

<property>

<name>mapred.child.java.opts</name>

<value>-Xmx1000m</value>

</property>