Timeout getting response from the server

java.lang.AssertionError: Timeout getting response from the server
	at org.junit.Assert.fail(Assert.java:88)
	at org.apache.spark.network.RpcIntegrationSuite.sendRPC(RpcIntegrationSuite.java:127)
	at org.apache.spark.network.RpcIntegrationSuite.doubleRPC(RpcIntegrationSuite.java:142)