Amazon Managed Service for Apache Flink was previously known as Amazon Kinesis Data Analytics for Apache Flink.
Apache Flink settings
Managed Service for Apache Flink is an implementation of the Apache Flink framework. Managed Service for Apache Flink uses the default values described in this section. Some of these values can be set by the Managed Service for Apache Flink applications in code, and others cannot be changed.
Use the links in this section to learn more about Apache flink settings and which ones are modifiable.
This topic contains the following sections:
Apache Flink configuration
Managed Service for Apache Flink provides a default Flink configuration consisting of Apache
Flink-recommended values for most properties and a few based on common application
profiles. For more information about Flink configuration, see Configuration
State backend
Managed Service for Apache Flink stores transient data in a state backend. Managed Service for Apache Flink uses the RocksDBStateBackend. Calling setStateBackend to set a different backend has no effect.
We enable the following features on the state backend:
Incremental state backend snapshots
Asynchronous state backend snapshots
Local recovery of checkpoints
For more information about state backends, see State Backends
Checkpointing
Managed Service for Apache Flink uses a default checkpoint configuration with the following values.
Some of these values can be changed using CheckpointConfiguration. You must set
CheckpointConfiguration.ConfigurationType to CUSTOM for
Managed Service for Apache Flink to use modified checkpointing values.
| Setting | Can be modified? | How | Default Value |
|---|---|---|---|
| CheckpointingEnabled | Modifiable | True | |
| CheckpointInterval | Modifiable | 60000 | |
| MinPauseBetweenCheckpoints | Modifiable | 5000 | |
| Unaligned checkpoints | Modifiable | Support case |
False |
| Number of Concurrent Checkpoints | Not Modifiable | N/A | 1 |
| Checkpointing Mode | Not Modifiable | N/A | Exactly Once |
| Checkpoint Retention Policy | Not Modifiable | N/A | On Failure |
| Checkpoint Timeout | Not Modifiable | N/A | 60 minutes |
| Max Checkpoints Retained | Not Modifiable | N/A | 1 |
| Checkpoint and Savepoint Location | Not Modifiable | N/A | We store durable checkpoint and savepoint data to a service-owned S3 bucket. |
Savepointing
By default, when restoring from a savepoint, the resume operation will try to map all state of the savepoint back to the program you are restoring with. If you dropped an operator,
by default, restoring from a savepoint that has data that corresponds to the missing operator will fail. You can allow the operation
to succeed by setting the AllowNonRestoredState parameter of the application's
FlinkRunConfiguration to true. This will
allow the resume operation to skip state that cannot be mapped to the new program.
For more information, see
Allowing Non-Restored State
Heap sizes
Managed Service for Apache Flink allocates each KPU 3 GiB of JVM heap, and reserves 1 GiB for native code allocations. For information about increasing your application capacity, see Implement application scaling in Managed Service for Apache Flink.
For more information about JVM heap sizes, see Configuration
Buffer debloating
Buffer debloating can help applications with high backpressure. If your application experiences failed checkpoints/savepoints, enabling this feature could be useful.
To do this, request a support case
For more information, see The Buffer Debloating Mechanism
