Hey Martijn,
The version is 1.16.0
On Wed, Mar 29, 2023 at 5:43 PM Martijn Visser <martijnvis...@apache.org>
wrote:
> Hi Reem,
>
> What's the Flink version where you're encountering this issue?
>
> Best regards,
>
> Martijn
>
> On Wed, Mar 29, 2023 at 5:18 PM Reem Razak via user <user@flink.apache.org>
> wrote:
>
>> Hey there!
>>
>> We are seeing a second Flink pipeline encountering similar issues when
>> configuring both `withWatermarkAlignment` and `withIdleness`. The
>> unexpected behaviour gets triggered after a Kafka cluster failover. Any
>> thoughts on there being an incompatibility between the two?
>>
>> Thanks!
>>
>> On Wed, Nov 9, 2022 at 6:42 PM Reem Razak <reem.ra...@shopify.com> wrote:
>>
>>> Hi there,
>>>
>>> We are integrating the watermark alignment feature into a pipeline with
>>> a Kafka source during a "backfill"- i.e. playing from an earlier Kafka
>>> offset. While testing, we noticed some unexpected behaviour in the
>>> watermark advancement which was resolved by removing `withIdleness` from
>>> our watermark strategy.
>>>
>>>
>>> val watermarkStrategy = WatermarkStrategy
>>> .forBoundedOutOfOrderness(Duration.ofMinutes(1))
>>> .withTimestampAssigner(new
>>> TimestampedEventTimestampAssigner[Event])
>>> .withWatermarkAlignment("alignment-group-1", Duration.ofMinutes(1))
>>> .withIdleness(Duration.ofMinutes(5))
>>>
>>> I have attached a couple of screenshots of the watermarkAlignmentDrift
>>> metric. As you can see, the behaviour seems normal until a sudden drop in
>>> the value to ~ Long.MIN_VALUE, which causes the pipeline to stop emitting
>>> records completely from the source. Furthermore, the logs originating from
>>> from
>>> https://github.com/dawidwys/flink/blob/888162083fbb5f62f809e5270ad968db58cc9c5b/flink-runtime/src/main/java/org/apache/flink/runtime/source/coordinator/SourceCoordinator.java#L174
>>> also indicate that the `maxAllowedWatermark` switches to ~ Long.MIN_VALUE.
>>>
>>> We found that modifying the `updateInterval` passed into the alignment
>>> parameters seemed to correlate with how long the pipeline would operate
>>> before stopping - a larger interval of 20 minutes would encounter the issue
>>> later than an interval of 1 second.
>>>
>>> We are wondering if a bug exists when using both `withIdleness` and
>>> `withWatermarkAlignment`. Might it be related to
>>> https://issues.apache.org/jira/browse/FLINK-28975, or is there possibly
>>> a race condition in the watermark emission? We do not necessarily need to
>>> have both configured at the same time, but we were also surprised by the
>>> behaviour of the application. Has anyone run into a similar issue or have
>>> further insight?
>>>
>>> Much Appreciated,
>>> - Reem
>>>
>>>
>>>
>>>
