event time and late events - documentation

[Sofer, Tovi]

Hi group,

Can someone please elaborate on the comment at the end of section “Debugging Windows & Event Time”?

Didn’t understand it meaning.

https://ci.apache.org/projects/flink/flink-docs-master/monitoring/debugging_event_time.html

“Handling Event Time Stragglers

Approach 1: Watermark stays late (indicated completeness), windows fire early

Approach 2: Watermark heuristic with maximum lateness, windows accept late data”

 

Thanks,

Tovi

[Elias Levy]

Tovi,

The document here should answer your question.  If it doesn't, please let me know.

On Mon, Jul 16, 2018 at 5:17 AM Sofer, Tovi <[hidden email]> wrote:

Hi group,

Can someone please elaborate on the comment at the end of section “Debugging Windows & Event Time”?

Didn’t understand it meaning.

https://ci.apache.org/projects/flink/flink-docs-master/monitoring/debugging_event_time.html

“Handling Event Time Stragglers

Approach 1: Watermark stays late (indicated completeness), windows fire early

Approach 2: Watermark heuristic with maximum lateness, windows accept late data”

 

Thanks,

Tovi

[vino yang]

Hi Tovi,

1. approach 1 : change the watermark let it means the later time, window trigger early.

2. approach 2 : do not change the watermark, but specify the allow lateness for the window[1][2], this way can make window accept late element and re-fire the window after watermark.

[1]: https://ci.apache.org/projects/flink/flink-docs-master/dev/event_time.html#late-elements

[2]: https://ci.apache.org/projects/flink/flink-docs-master/dev/stream/operators/windows.html#allowed-lateness

Thanks, vino.

2018-07-16 23:28 GMT+08:00 Elias Levy <[hidden email]>:

Tovi,

The document here should answer your question.  If it doesn't, please let me know.

On Mon, Jul 16, 2018 at 5:17 AM Sofer, Tovi <[hidden email]> wrote:

Hi group,

Can someone please elaborate on the comment at the end of section “Debugging Windows & Event Time”?

Didn’t understand it meaning.

https://ci.apache.org/projects/flink/flink-docs-master/monitoring/debugging_event_time.html

“Handling Event Time Stragglers

Approach 1: Watermark stays late (indicated completeness), windows fire early

Approach 2: Watermark heuristic with maximum lateness, windows accept late data”

 

Thanks,

Tovi