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Hii All
I have a basic doubt around watermark generation.
Let's say I have a kafka topic with 10 partitions and if I provide source parallelism to be 15, with idleTimeout of 30 mins.
In this case, how are the watermarks generated ?
1. Does it hold back watermark due 5 (15-10) idle slots till 30 mins ?
2. Or it identifies that kafka partition count is 10 and hence progress the watermark.
I am observing that it shows `No Watermark (Watermarks are only available if EventTime is used)` for quite some time and then starts generating watermark.

The KafkaSource will indeed wait for the idle timeout before progressing the watermark.

Yes David, it holds back the watermark till idleTimeout passes.
So does it mean we *must* provide source parallelism equal to kafka partitions, and never more than that ?

If you are using `BoundedOutOfOrderness` , then you can specify like
```    val watermarkStrategy: WatermarkStrategy[Option[T]] = WatermarkStrategy
      .forBoundedOutOfOrderness(Duration.ofSeconds(maxOutOfOrdernessInSecs))
      .withIdleness(Duration.ofSeconds(idlenessInSecs))```

You can apply it on any WatermarkStrategy using `.withIdleness`