dawidwys commented on a change in pull request #15687: URL: https://github.com/apache/flink/pull/15687#discussion_r617274868
########## File path: docs/content.zh/release-notes/flink-1.13.md ########## @@ -0,0 +1,248 @@ +--- +title: "Release Notes - Flink 1.13" +--- +<!-- +Licensed to the Apache Software Foundation (ASF) under one +or more contributor license agreements. See the NOTICE file +distributed with this work for additional information +regarding copyright ownership. The ASF licenses this file +to you under the Apache License, Version 2.0 (the +"License"); you may not use this file except in compliance +with the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, +software distributed under the License is distributed on an +"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +KIND, either express or implied. See the License for the +specific language governing permissions and limitations +under the License. +--> + +# Release Notes - Flink 1.13 + +These release notes discuss important aspects, such as configuration, behavior, or dependencies, +that changed between Flink 1.12 and Flink 1.13. Please read these notes carefully if you are +planning to upgrade your Flink version to 1.13. + +### Failover + +#### Remove `state.backend.async` option. + +##### [FLINK-21935](https://issues.apache.org/jira/browse/FLINK-21935) + +The `state.backend.async` option is deprecated. Snapshots are always asynchronous now (as they were +by default before) and there is no option to configure a synchronous snapshot any more. + +The constructors of `FsStateBackend` and `MemoryStateBackend` that take a flag for sync/async +snapshots are kept for API compatibility, but the flags are ignored now. + +#### Unify Binary format for Keyed State savepoints + +##### [FLINK-20976](https://issues.apache.org/jira/browse/FLINK-20976) + +Flink’s savepoint binary format is unified across all state backends. That means you can take a +savepoint with one state backend and then restore it using another. + +If you want to switch the state backend you should first upgrade your Flink version to 1.13 then +take a savepoint with the new version, and only after that, you can restore it with a different +state backend. + +#### FailureRateRestartBackoffTimeStrategy allows one less restart than configured + +##### [FLINK-20752](https://issues.apache.org/jira/browse/FLINK-20752) + +The Failure Rate Restart Strategy was allowing 1 less restart per interval as configured. Users +wishing to keep the current behavior should reduce the maximum number of allowed failures per +interval by 1. + +#### Unaligned checkpoint recovery may lead to corrupted data stream + +##### [FLINK-20654](https://issues.apache.org/jira/browse/FLINK-20654) + +Using unaligned checkpoints in Flink 1.12.0 combined with two/multiple inputs tasks or with union +inputs for single input tasks can result in corrupted state. + +This can happen if a new checkpoint is triggered before recovery is fully completed. For state to be +corrupted a task with two or more input gates must receive a checkpoint barrier exactly at the same +time this task finishes recovering spilled in-flight data. In such case this new checkpoint can +succeed, with corrupted/missing in-flight data, which will result in various +deserialisation/corrupted data stream errors when someone attempts to recover from such corrupted +checkpoint. + +Using unaligned checkpoints in Flink 1.12.1, a corruption may occur in the checkpoint following a +declined checkpoint. + +A late barrier of a canceled checkpoint may lead to buffers being not written into the successive +checkpoint, such that recovery is not possible. This happens, when the next checkpoint barrier +arrives at a given operator before all previous barriers arrived, which can only happen after +cancellation in unaligned checkpoints. + +#### Support rescaling for Unaligned Checkpoints + +##### [FLINK-17979](https://issues.apache.org/jira/browse/FLINK-17979) + +While recovering from unaligned checkpoints, users can now change the parallelism of the job. This +change allows users to quickly upscale the job under backpressure. + +### SQL + +#### Officially deprecate the legacy planner + +##### [FLINK-21709](https://issues.apache.org/jira/browse/FLINK-21709) + +The old planner of the Table & SQL API is deprecated and will be dropped in Flink 1.14. This means +that both the BatchTableEnvironment and DataSet API interop are reaching end of life. Use the +unified TableEnvironment for batch and stream processing with the new planner, or the DataStream API +in batch execution mode. + +#### Disable problematic cast conversion between NUMERIC type and TIMESTAMP type + +##### [FLINK-21698](https://issues.apache.org/jira/browse/FLINK-21698) + +The CAST operation between `NUMERIC` type and `TIMESTAMP` type is problematic and is disabled now, +e.g. +`CAST(numeric AS TIMESTAMP(3))` is disabled and should use `TO_TIMESTAMP(FROM_UNIXTIME(numeric))` +instead. + +#### Support 'USE MODULES' syntax + +##### [FLINK-21298](https://issues.apache.org/jira/browse/FLINK-21298) + +The term MODULES is a reserved keyword now. Use backticks to escape column names and other +identifiers with this name. + +#### Update `TableResult.collect()/TableResult.print()` to the new type system + +##### [FLINK-20613](https://issues.apache.org/jira/browse/FLINK-20613) + +`Table.execute().collect()` might return slightly different results for column types and row kind. + +#### Update the Row.toString method + +##### [FLINK-18090](https://issues.apache.org/jira/browse/FLINK-18090) + +The Row.toSting method has been reworked. This is an incompatible change. If the legacy +representation is still required for tests, the old behavior can be restored via the flag +`RowUtils.USE_LEGACY_TO_STRING` for the local JVM. However, relying on the row's string +representation for tests is not a good idea in general as field data types are not verified. + +### Runtime + +#### BoundedOneInput.endInput is called when taking synchronous savepoint + +##### [FLINK-21132](https://issues.apache.org/jira/browse/FLINK-21132) + +`endInput()` is not called anymore (on BoundedOneInput and BoundedMultiInput) when the job is +stopping with savepoint. + +#### Remove JobManagerOptions.SCHEDULING_STRATEGY + +##### [FLINK-20591](https://issues.apache.org/jira/browse/FLINK-20591) + +The configuration parameter `jobmanager.scheduler.scheduling-strategy` has been removed, because +the `legacy` scheduler has been removed from Flink 1.13.0. + +#### Warn user if System.exit() is called in user code + +##### [FLINK-15156](https://issues.apache.org/jira/browse/FLINK-15156) + +A new configuration value `cluster.intercept-user-system-exit` allows to log a warning, or throw an +exception if user code calls `System.exit()`. + +This feature is not covering all locations in Flink where user code is executed. It just adds the +infrastructure for such an interception. + +### Docker + +#### Consider removing automatic configuration fo number of slots from docker + +##### [FLINK-21036](https://issues.apache.org/jira/browse/FLINK-21036) + +The docker images no longer set the default number of taskmanager slots to the number of CPU cores. +This behavior was inconsistent with all other deployment methods and ignored any limits on the CPU +usage set via docker. + +#### Rework jemalloc switch to use an environment variable + +##### [FLINK-21034](https://issues.apache.org/jira/browse/FLINK-21034) + +The docker switch for disabling the jemalloc memory allocator has been reworked from a script +argument to an environment variable called DISABLE_JEMALLOC. If set to "true" jemalloc will not be +enabled. + +### Connectors + +#### Remove swift FS filesystem + +##### [FLINK-21819](https://issues.apache.org/jira/browse/FLINK-21819) + +The Swift FileSystem is no longer being actively developed and has been removed from the project and +distribution. + +### Monitoring & debugging + +#### Introduce latency tracking state + +##### [FLINK-21736](https://issues.apache.org/jira/browse/FLINK-21736) + +State access latency metrics are introduced to track all kinds of keyed state access to help debug +state performance. This feature is not enabled by default and could be turned on once +setting `state.backend.latency-track.keyed-state-enabled` as true. + +#### Support for CPU FlameGraphs in new web UI Review comment: The titles are extracted from JIRA issues, I suppose back when the issue was created we had two UIs at the same time. -- This is an automated message from the Apache Git Service. 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