Exception in thread "main" org.apache.flink.runtime.client.JobExecutionException: Job execution failed.
	at org.apache.flink.runtime.jobmaster.JobResult.toJobExecutionResult(JobResult.java:146)
	at org.apache.flink.runtime.minicluster.MiniCluster.executeJobBlocking(MiniCluster.java:638)
	at org.apache.flink.streaming.api.environment.LocalStreamEnvironment.execute(LocalStreamEnvironment.java:123)
	at cn.crawler.mft_first.HotItems2.main(HotItems2.java:144)
Caused by: AsynchronousException{java.lang.Exception: Could not materialize checkpoint 14 for operator Window(SlidingEventTimeWindows(3600000, 180000), EventTimeTrigger, CountAgg, WindowResultFunction) (1/1).}
	at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointExceptionHandler.tryHandleCheckpointException(StreamTask.java:1153)
	at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.handleExecutionException(StreamTask.java:947)
	at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:884)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.Exception: Could not materialize checkpoint 14 for operator Window(SlidingEventTimeWindows(3600000, 180000), EventTimeTrigger, CountAgg, WindowResultFunction) (1/1).
	at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.handleExecutionException(StreamTask.java:942)
	... 6 more
Caused by: java.util.concurrent.ExecutionException: java.io.IOException: Size of the state is larger than the maximum permitted memory-backed state. Size=14068058 , maxSize=5242880 . Consider using a different state backend, like the File System State backend.
	at java.util.concurrent.FutureTask.report(FutureTask.java:122)
	at java.util.concurrent.FutureTask.get(FutureTask.java:192)
	at org.apache.flink.runtime.concurrent.FutureUtils.runIfNotDoneAndGet(FutureUtils.java:394)
	at org.apache.flink.streaming.api.operators.OperatorSnapshotFinalizer.<init>(OperatorSnapshotFinalizer.java:47)
	at org.apache.flink.streaming.runtime.tasks.StreamTask$AsyncCheckpointRunnable.run(StreamTask.java:853)
	... 5 more
Caused by: java.io.IOException: Size of the state is larger than the maximum permitted memory-backed state. Size=14068058 , maxSize=5242880 . Consider using a different state backend, like the File System State backend.
	at org.apache.flink.runtime.state.memory.MemCheckpointStreamFactory.checkSize(MemCheckpointStreamFactory.java:64)
	at org.apache.flink.runtime.state.memory.MemCheckpointStreamFactory$MemoryCheckpointOutputStream.closeAndGetBytes(MemCheckpointStreamFactory.java:145)
	at org.apache.flink.runtime.state.memory.MemCheckpointStreamFactory$MemoryCheckpointOutputStream.closeAndGetHandle(MemCheckpointStreamFactory.java:126)
	at org.apache.flink.runtime.state.CheckpointStreamWithResultProvider$PrimaryStreamOnly.closeAndFinalizeCheckpointStreamResult(CheckpointStreamWithResultProvider.java:77)
	at org.apache.flink.runtime.state.heap.HeapSnapshotStrategy$1.callInternal(HeapSnapshotStrategy.java:199)
	at org.apache.flink.runtime.state.heap.HeapSnapshotStrategy$1.callInternal(HeapSnapshotStrategy.java:158)
	at org.apache.flink.runtime.state.AsyncSnapshotCallable.call(AsyncSnapshotCallable.java:75)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at org.apache.flink.runtime.concurrent.FutureUtils.runIfNotDoneAndGet(FutureUtils.java:391)
	... 7 more

Process finished with exit code 1