Re: Does Flink DataStreams using combiners?

I think combiners would be a great addition to "aligned windows". On Fri, Aug 12, 2016 at 11:11 AM, Aljoscha Krettek wrote: > Hi, > Sameer is right that Flink currently does not combine for any combination > of assigner, trigger and window function. > > Technically, it

Re: Does Flink DataStreams using combiners?

Hi, Sameer is right that Flink currently does not combine for any combination of assigner, trigger and window function. Technically, it would be possible to use a combiner for Triggers that don't observe individual elements but only fire on time. With triggers that observe elements, such as

Re: Does Flink DataStreams using combiners?

Streaming cannot use windows. The aggregations happen on the trigger. The elements being aggregated are only known after the trigger delivers the elements to the evaluation function. Since windows can overlap and even assignment to a window is not done until the elements arrive at the sum

Re: Does Flink DataStreams using combiners?

Sorry I mean streaming cannot use combiners (repeated below) --- Streaming cannot use combiners. The aggregations happen on the trigger. The elements being aggregated are only known after the trigger delivers the elements to the evaluation function. Since windows can overlap and even

Does Flink DataStreams using combiners?

I am wondering if Flink makes use of combiners to pre-reduce a keyed and windowed stream before shuffling the data among workers. I.e. will it use a combiner in something like: stream.flatMap {...} .assignTimestampsAndWatermarks(...) .keyBy(...) .timeWindow(...)