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From Rico Bergmann <i...@ricobergmann.de>
Subject Performance Issue
Date Mon, 07 Sep 2015 10:00:18 GMT

While working with grouping and windowing I encountered a strange behavior. I'm doing:
> dataStream.groupBy(KeySelector).window(Time.of(x, TimeUnit.SECONDS)).mapWindow(toString).flatten()

When I run the program containing this snippet it initially outputs data at a rate around
150 events per sec. (That is roughly the input rate for the program). After about 10-30 minutes
the rate drops down below 5 events per sec. This leads to event delivery offsets getting bigger
and bigger ... 

Any explanation for this? I know you are reworking the streaming API. But it would be useful
to know, why this happens ...

Cheers. Rico. 
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