Re: Stateful functions 2.2 and stop with savepoint

Posted by Piotr Nowojski-5 on
URL: http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/Stateful-functions-2-2-and-stop-with-savepoint-tp41772p41926.html

Hi Meissner,

Can you clarify, are you talking about stateful functions? [1] Or the stream iterations [2]? The first e-mail suggests stateful functions, but the ticket that Kezhu created is talking about the latter.

Piotrek

[1] https://flink.apache.org/news/2020/04/07/release-statefun-2.0.0.html

[2] https://ci.apache.org/projects/flink/flink-docs-stable/dev/datastream_api.html#iterations

niedz., 28 lut 2021 o 15:33 Kezhu Wang <[hidden email]> napisał(a):

Hi,

You could also try `cancel —withSavepoint [savepointDir]` even it is in deprecation. Comparing to take-savepoints and then cancel approach, there will be no checkpoints in between. This may be important if there are two phase commit operators in your job.

Best,

Kezhu Wang

On February 28, 2021 at 20:50:29, Meissner, Dylan ([hidden email]) wrote:

Thank you for opening the bug and including the extra context.

I'll track the progress and, in the meantime, I will work around by taking two separate actions when stopping job: take-savepoints, then cancel.

---

From: Kezhu Wang <[hidden email]>
Sent: Sunday, February 28, 2021 12:31 AM
To: [hidden email] <[hidden email]>; Meissner, Dylan <[hidden email]>
Subject: Re: Stateful functions 2.2 and stop with savepoint

 

Hi,

Thanks for reporting. I think it is a Flink bug and have created FLINK-21522 for it. You could track progress there.

FLINK-21522: https://issues.apache.org/jira/browse/FLINK-21522

Best,

Kezhu Wang

On February 28, 2021 at 00:59:04, Meissner, Dylan ([hidden email]) wrote:

I have an embedded function with a SinkFunction as an egress, implemented as this pseudo-code:

val serializationSchema = KafkaSchemaSerializationSchema(... props required to use a Confluent Schema Registry with Avro, auth etc ...)

return SinkFunctionSpec(EGRESS_ID, FlinkKafkaProducer(serializationSchema, props, AT_LEAST_ONCE))

Checkpointing and taking a savepoint without stopping work as expected.

However, when I run "flink stop <job-id>" or even "flink stop --drain <job-id>", the operation never completes, reporting IN_PROGRESS until I hit the "failure-cause: org.apache.flink.runtime.checkpoint.CheckpointException: Checkpoint expired before completing" CompletedException.

In the "Checkpoint History" it shows only 2 of my 3 operators completed their work:

Source: my-ingress-ingress -> router (my-ingress) | acknowledge: 1/1 (100%) | end-to-end duration: 638ms | data-size 1.38 KB
feedback-union -> functions -> Sink: my-egress-egress | acknowledge 0/1 0% | end-to-end duration: n/a | data-size: n/a

feedback | acknowledge: 1/1 (100%) | end-to-end duration: 626ms | data-size: 0 B

I've been unable to gain any insights from logs so far. Thoughts?