Re: Are RocksDBWindowStore windows hopping or sliding?

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What you call "sliding window" is called "hopping window" in Kafka Streams.

And yes, you can use a windowed-store for this case: In fact, a
non-overlapping tumbling window is just a special case of a hopping
window with advance == window-size.

In Kafka Streams we have a single implementation for hopping windows
(that we use for tumbling windows, too):
https://github.com/apache/kafka/blob/trunk/streams/src/main/java/org/apache/kafka/streams/kstream/internals/KStreamWindowAggregate.java


-Matthias

On 2/26/20 9:47 PM, Sachin Mittal wrote:
> Hi,
> So far how I have understood is that when we create a rocksdb window store;
> we specify a window size and retention period.
>
> So windows are created from epoch time based on size, say size if 100 then
> windows are:
> [0, 100), [100, 200), [200, 300) ...
>
> Windows are retained based on retention period and after which it is
> dropped.
>
> Also a window is divided into segments which is implemented using a treemap.
>
> Please confirm if my understanding is correct.
>
> Also looks from all this is that windows are always hopping.
>
> Is there a case of sliding windows that can be created? If yes how?
> Example of sliding window would be:
> [0, 100), [75, 175), [150, 250) ...
>
> Thanks
> Sachin
>