Hi,
We are trying to test the recovery mechanism of Flink with Kafka and HDFS sink
during failures.
I’ve killed the job after processing some messages and restarted the same job
again. Some of the messages I am seeing are processed more than once and not
following the exactly once semantics.
Also, using the checkpointing mechanism and saving the state checkpoints into
HDFS.
Below is the checkpoint code,
envStream.enableCheckpointing(11);
envStream.getCheckpointConfig().setCheckpointingMode(CheckpointingMode.EXACTLY_ONCE);
envStream.getCheckpointConfig().setCheckpointTimeout(60000);
envStream.getCheckpointConfig().setMaxConcurrentCheckpoints(4);
envStream.setStateBackend(new
FsStateBackend("hdfs://ipaddr/mount/cp/checkpoint/"));
One thing I’ve noticed is lowering the time to checkpointing is actually
lowering the number of messages processed more than once and 11ms is the lowest
I can use.
Is there anything else I should try to have exactly once message processing
functionality.
I am using Flink 1.0.0 and kafka 0.8
Thank you.
________________________________________________________
The information contained in this e-mail is confidential and/or proprietary to
Capital One and/or its affiliates and may only be used solely in performance of
work or services for Capital One. The information transmitted herewith is
intended only for use by the individual or entity to which it is addressed. If
the reader of this message is not the intended recipient, you are hereby
notified that any review, retransmission, dissemination, distribution, copying
or other use of, or taking of any action in reliance upon this information is
strictly prohibited. If you have received this communication in error, please
contact the sender and delete the material from your computer.
