Hi 对于问题 1 在反压的情况下，可能导致 Savepoint 做不成功从而超时，这个暂时没法解决，现在有一个 issue[1] 在做 Unalign Checkpoint 可以解决反压情况下的 checkpoint 对于问题 3，checkpoint 超时了，超时的定义：在设置的时间内（比如你这里 5 分钟），有 task 没有完成 snapshot。调长超时时间能够一定的缓解这个问题，不过你最好找到超时的原因，然后针对性的优化。 [1] https://issues.apache.org/jira/browse/FLINK-14551 Best, Congxian
大数据开发面试_夏永权 <[email protected]> 于2020年3月27日周五 下午4:19写道： > Hi，您好，在使用flink的过程中遇到如下问题，个人未能解决，所以请求您指导一下，谢谢！ > > 1. flink cancel -s $SAVEPOINT_DIR $job_id -yid $application_id > 在程序有背压的时候停不掉 > > > The program finished with the following exception: > org.apache.flink.util.FlinkException: Could not cancel job > 1f768e4ca9ad5792a4844a5d12163b73. > at > org.apache.flink.client.cli.CliFrontend.lambda$cancel$6(CliFrontend.java:523) > at > org.apache.flink.client.cli.CliFrontend.runClusterAction(CliFrontend.java:843) > at org.apache.flink.client.cli.CliFrontend.cancel(CliFrontend.java:515) > at > org.apache.flink.client.cli.CliFrontend.parseParameters(CliFrontend.java:904) > at > org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:968) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:422) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692) > at > org.apache.flink.runtime.security.HadoopSecurityContext.runSecured(HadoopSecurityContext.java:41) > at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:968) > Caused by: java.util.concurrent.TimeoutException > at > java.util.concurrent.CompletableFuture.timedGet(CompletableFuture.java:1771) > at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1915) > at > org.apache.flink.client.cli.CliFrontend.lambda$cancel$6(CliFrontend.java:521) > ... 9 more > stop flink job failed!!! > > > > > 2.再用flink > sql的ddl时候增加一个字段后，程序启动失败，需要删除savepoint才能启动(ddl后双流join的逻辑，其中一个流加了一个字段) > > > The program finished with the following exception: > org.apache.flink.client.program.ProgramInvocationException: The main > method caused an error: > org.apache.flink.runtime.concurrent.FutureUtils$RetryException: Could not > complete the operation. Number of retries has been exhausted. > at > org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:335) > at > org.apache.flink.client.program.PackagedProgram.invokeInteractiveModeForExecution(PackagedProgram.java:205) > at org.apache.flink.client.ClientUtils.executeProgram(ClientUtils.java:138) > at > org.apache.flink.client.cli.CliFrontend.executeProgram(CliFrontend.java:664) > at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:213) > at > org.apache.flink.client.cli.CliFrontend.parseParameters(CliFrontend.java:895) > at > org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:968) > at java.security.AccessController.doPrivileged(Native Method) > at javax.security.auth.Subject.doAs(Subject.java:422) > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1692) > at > org.apache.flink.runtime.security.HadoopSecurityContext.runSecured(HadoopSecurityContext.java:41) > at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:968) > Caused by: java.util.concurrent.ExecutionException: > org.apache.flink.runtime.concurrent.FutureUtils$RetryException: Could not > complete the operation. Number of retries has been exhausted. > at > java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357) > at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1895) > at > org.apache.flink.streaming.api.environment.StreamContextEnvironment.execute(StreamContextEnvironment.java:83) > at > org.apache.flink.streaming.api.environment.StreamExecutionEnvironment.execute(StreamExecutionEnvironment.java:1620) > at > com.etl.DwdBaseCarlifeTIotBindGeoManage.main(DwdBaseCarlifeTIotBindGeoManage.java:265) > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > at > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > at java.lang.reflect.Method.invoke(Method.java:498) > at > org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:321) > ... 11 more > Caused by: org.apache.flink.runtime.concurrent.FutureUtils$RetryException: > Could not complete the operation. Number of retries has been exhausted. > at > org.apache.flink.runtime.concurrent.FutureUtils.lambda$retryOperationWithDelay$8(FutureUtils.java:284) > at > java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:760) > at > java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:736) > at > java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:474) > at > java.util.concurrent.CompletableFuture.completeExceptionally(CompletableFuture.java:1977) > at > org.apache.flink.runtime.rest.RestClient.lambda$submitRequest$1(RestClient.java:342) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:500) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:493) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:472) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:413) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:538) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.setFailure0(DefaultPromise.java:531) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.DefaultPromise.tryFailure(DefaultPromise.java:111) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:323) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:339) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:685) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:632) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:549) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:511) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:918) > at > org.apache.flink.shaded.netty4.io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) > at java.lang.Thread.run(Thread.java:748) > Caused by: java.util.concurrent.CompletionException: > org.apache.flink.shaded.netty4.io.netty.channel.AbstractChannel$AnnotatedConnectException: > Connection refused:/10.*.*.*:42666 > at > java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:292) > at > java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:308) > at > java.util.concurrent.CompletableFuture.uniCompose(CompletableFuture.java:943) > at > java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:926) > ... 19 more > Caused by: > org.apache.flink.shaded.netty4.io.netty.channel.AbstractChannel$AnnotatedConnectException: > Connection refused:centos/10.*.*:42666 > Caused by: java.net.ConnectException: Connection refused > at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) > at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717) > at > org.apache.flink.shaded.netty4.io.netty.channel.socket.nio.NioSocketChannel.doFinishConnect(NioSocketChannel.java:327) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:336) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:685) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:632) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:549) > at > org.apache.flink.shaded.netty4.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:511) > at > org.apache.flink.shaded.netty4.io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:918) > at > org.apache.flink.shaded.netty4.io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) > at java.lang.Thread.run(Thread.java:748) > > > > > 3.flink > checkpoint超时问题，我之前的checkpoint间隔是3分钟，超时时间是5分钟，报了如下错误，而且job与taskmanager都不挂，很难监控。 > 现在checkpoint间隔调整成2分钟，超时时间是10分钟，不知是否会解决。 > Checkpoint 298 of job 1f768e4ca9ad5792a4844a5d12163b73 expired before > completing.
