Address already in use: Service 'SparkUI' failed after 16 retries

java.net.BindException: Address already in use: Service 'SparkUI' failed after 16 retries!
at sun.nio.ch.Net.bind0(Native Method)
at sun.nio.ch.Net.bind(Net.java:444)
at sun.nio.ch.Net.bind(Net.java:436)
at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:214)
at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
at org.eclipse.jetty.server.nio.SelectChannelConnector.open(SelectChannelConnector.java:187)
at org.eclipse.jetty.server.AbstractConnector.doStart(AbstractConnector.java:316)
at org.eclipse.jetty.server.nio.SelectChannelConnector.doStart(SelectChannelConnector.java:265)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)

错误原因：

Spark任务提交时会占用一个SparkUI端口，默认为4040，如果被占用则依次递增端口重试。但是有个默认重试次数，为16次。16次重试都失败后，会放弃该任务的运行。

解决方案：

加上参数：-- conf.set(“spark.port.maxRetries”,“100”)