Order by which windows are processed on event time

[Saiph Kappa]

Hi,

I have a streaming application based on event time. When I issue a watermark that will close more than 1 window (and trigger their processment), I can see that windows are computed sequentially (at least using local machine) and that the computing order is not defined. Can I change this behavior to make it compute from the oldest to the newest window? Where in the flink code can I find this that handles the scheduling of window processment?

Thank you.

[Ufuk Celebi]

I think there are no ordering guarantees for this. @Aljoscha: is this correct?


On 11 November 2016 at 19:57:43, Saiph Kappa ([hidden email]) wrote:

> Hi,
>
> I have a streaming application based on event time. When I issue a
> watermark that will close more than 1 window (and trigger their
> processment), I can see that windows are computed sequentially (at least
> using local machine) and that the computing order is not defined. Can I
> change this behavior to make it compute from the oldest to the newest
> window? Where in the flink code can I find this that handles the scheduling
> of window processment?
>
> Thank you.
>

[Aljoscha Krettek]

Hi,

event-time windows are being processed in the order of their end timestamp. If several windows have the same end timestamp then no ordering across those windows is guaranteed.

Cheers,

Aljoscha

On Mon, 14 Nov 2016 at 10:01 Ufuk Celebi <[hidden email]> wrote:

I think there are no ordering guarantees for this. @Aljoscha: is this correct?


On 11 November 2016 at 19:57:43, Saiph Kappa ([hidden email]) wrote:
> Hi,
>
> I have a streaming application based on event time. When I issue a
> watermark that will close more than 1 window (and trigger their
> processment), I can see that windows are computed sequentially (at least
> using local machine) and that the computing order is not defined. Can I
> change this behavior to make it compute from the oldest to the newest
> window? Where in the flink code can I find this that handles the scheduling
> of window processment?
>
> Thank you.
>