Found the reason: it does not work together with
.withIdleness(Duration.ofSeconds(1))
Isn't this a valid scenario: one subtask has multiple input streams/channels
where some are idle, others have large watermark skews?
In addition, do we expect that the watermark update interval in:
.withWatermarkAlignment("wm-group", maxDrift, updateInterval)
to be at the milli second level? If so, the following log msg should be at the
DEBUG level, I think
2022-07-10 06:53:35,713 INFO
org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - Distributing
maxAllowedWatermark=-9223372036854765808 to subTaskIds=[]
to avoid streaming logs filling up the disk space.
Thanks
Jun
> On Jul 10, 2022, at 9:10 AM, Jun Qin wrote:
>
> Hi All
>
> I am trying watermark alignment in Flink 1.15 with:
>
> watermarkStrategy = WatermarkStrategy.<~>forBoundedOutOfOrderness(
> Duration.ofMillis(outOfOrderness))
> .withWatermarkAlignment("wm-group", Duration.ofSeconds(10),
> Duration.ofSeconds(1))
> .withTimestampAssigner(
> (element, timestamp) -> element.getTimestamp())
> .withIdleness(Duration.ofSeconds(1));
>
> And got the following in DEBUG logs:
> 2022-07-10 06:53:35,713 INFO
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] -
> Distributing maxAllowedWatermark=-9223372036854765808 to subTaskIds=[]
> 2022-07-10 06:53:36,606 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 1657436016036 (2022-07-10 06:53:36.036) from
> subTaskId=2
> 2022-07-10 06:53:36,619 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 1657435956048 (2022-07-10 06:52:36.048) from
> subTaskId=1
> 2022-07-10 06:53:36,639 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 1657436016034 (2022-07-10 06:53:36.034) from
> subTaskId=3
> 2022-07-10 06:53:36,702 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 1657436016053 (2022-07-10 06:53:36.053) from
> subTaskId=0
> 2022-07-10 06:53:36,713 INFO
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] -
> Distributing maxAllowedWatermark=1657435966048 to subTaskIds=[0, 1, 2, 3]
> 2022-07-10 06:53:37,229 DEBUG
> shaded.io.kubernetes.client.extended.leaderelection.LeaderElector [] - Update
> lock acquire time to keep lease
> 2022-07-10 06:53:37,237 DEBUG
> shaded.io.kubernetes.client.extended.leaderelection.LeaderElector [] -
> TryAcquireOrRenew return success
> 2022-07-10 06:53:37,237 DEBUG
> shaded.io.kubernetes.client.extended.leaderelection.LeaderElector [] -
> Successfully renewed lease
> 2022-07-10 06:53:37,603 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=2
> 2022-07-10 06:53:37,605 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=3
> 2022-07-10 06:53:37,616 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=1
> 2022-07-10 06:53:37,630 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=0
> 2022-07-10 06:53:37,713 INFO
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] -
> Distributing maxAllowedWatermark=-9223372036854765809 to subTaskIds=[0, 1, 2,
> 3]
> 2022-07-10 06:53:38,603 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=2
> 2022-07-10 06:53:38,604 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=3
> 2022-07-10 06:53:38,616 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=1
> 2022-07-10 06:53:38,630 DEBUG
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] - New
> reported watermark=Watermark @ 9223372036854775807 (292278994-08-17
> 07:12:55.807) from subTaskId=0
> 2022-07-10 06:53:38,713 INFO
> org.apache.flink.runtime.source.coordinator.SourceCoordinator [] -
> Distributing maxAllowedWatermark=-9223372036854765809 to subTaskIds=[0, 1, 2,
> 3]
>
>
> Then it stays with maxAllowedWatermark=-9223372036854765809 all the time. The
> watermark looks to be correct at beginning, then