我有两个关于 Flink 外部化检查点的问题
(Q1( 我可以在 flink-conf.yaml 中设置"state.checkpoints.dir"以使外部化的检查点正常工作，但是当我从 IDE 运行 flink 时，我如何实现同样的事情？我尝试了(http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/state-checkpoints-dir-td17921.html(中提到的全局配置方法，但没有运气。我是这样做的：
Configuration cfg =
GlobalConfiguration.loadConfiguration();
cfg.setString("state.checkpoints.dir", "file:///tmp/checkpoints/state");
env.getCheckpointConfig().enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
这是IDE中显示的错误消息：
Exception in thread "main" org.apache.flink.runtime.client.JobExecutionException: Failed to submit job ef7050e2308a4787d983d80f3c07f55c (Long Taxi Rides (checkpointed))
at org.apache.flink.runtime.jobmanager.JobManager.org$apache$flink$runtime$jobmanager$JobManager$$submitJob(JobManager.scala:1325)
at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1.applyOrElse(JobManager.scala:447)
at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:36)
at org.apache.flink.runtime.LeaderSessionMessageFilter$$anonfun$receive$1.applyOrElse(LeaderSessionMessageFilter.scala:38)
at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:36)
at org.apache.flink.runtime.LogMessages$$anon$1.apply(LogMessages.scala:33)
at org.apache.flink.runtime.LogMessages$$anon$1.apply(LogMessages.scala:28)
at scala.PartialFunction$class.applyOrElse(PartialFunction.scala:123)
at org.apache.flink.runtime.LogMessages$$anon$1.applyOrElse(LogMessages.scala:28)
at akka.actor.Actor$class.aroundReceive(Actor.scala:502)
at org.apache.flink.runtime.jobmanager.JobManager.aroundReceive(JobManager.scala:122)
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:526)
at akka.actor.ActorCell.invoke(ActorCell.scala:495)
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:257)
at akka.dispatch.Mailbox.run(Mailbox.scala:224)
at akka.dispatch.Mailbox.exec(Mailbox.scala:234)
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: java.lang.IllegalStateException: CheckpointConfig says to persist periodic checkpoints, but no checkpoint directory has been configured. You can configure configure one via key 'state.checkpoints.dir'.
at org.apache.flink.runtime.checkpoint.CheckpointCoordinator.<init>(CheckpointCoordinator.java:211)
at org.apache.flink.runtime.executiongraph.ExecutionGraph.enableCheckpointing(ExecutionGraph.java:478)
at org.apache.flink.runtime.executiongraph.ExecutionGraphBuilder.buildGraph(ExecutionGraphBuilder.java:291)
at org.apache.flink.runtime.jobmanager.JobManager.org$apache$flink$runtime$jobmanager$JobManager$$submitJob(JobManager.scala:1277)
... 19 more
Process finished with exit code 1
(Q2( 在检查点的文档 (https://ci.apache.org/projects/flink/flink-docs-release-1.4/dev/stream/state/checkpointing.html( 中，它说"这样，如果您的作业失败，您将有一个检查点可以从中恢复。 取消的作业怎么样？ 新作业是继续使用现有检查点，还是从自己的检查点开始？
您可以控制在取消作业时是否删除外部化检查点。如果要保留它们，可以执行以下操作：
CheckpointConfig config = env.getCheckpointConfig();
config.enableExternalizedCheckpoints(ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
有关详细信息，请参阅文档。
要从外部化检查点恢复，请执行以下操作(与从保存点恢复相同(：
$ bin/flink run -s :checkpointMetaDataPath [:runArgs]
第一个问题，使用自定义配置创建本地环境：
val conf = new Configuration()
conf.setString(CoreOptions.CHECKPOINTS_DIRECTORY, "file:///user/flink/checkpoint/storing/")
StreamExecutionEnvironment.createLocalEnvironment(4, conf)
第二个问题，正如大卫所说：
config.enableExternalizedCheckpoints(ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
从 Eclipse 重新设置检查点目录，通常我只是在设置要使用的后端时执行此操作，例如
env.setStateBackend(new FsStateBackend(options.getCheckpointDir()));
重新取消作业 - 检查点目录被删除。如果要在停止(取消(作业后从已知状态恢复，则需要执行保存点。