Hi, I don’t have any hard numbers for this, and it depends on what kind of state backend is used (Heap backend or RocksDB backend).
Iterations are documented in the Flink doc: https://ci.apache.org/projects/flink/flink-docs-release-1.3/dev/datastream_api.html#iterations <https://ci.apache.org/projects/flink/flink-docs-release-1.3/dev/datastream_api.html#iterations> Essentially what they allow is to have a processing graph that is not a DAG. This can be useful in machine learning use cases where you want to feed back some information to an earlier operation to update a model. Best, Aljoscha > On 4. Apr 2017, at 09:46, amir bahmanyari <amirto...@yahoo.com> wrote: > > Thanks Aljoscha, > How sever of performance difference are we talking about here? > examples of "Iterations/feedback edges" and how they get applied? > Thanks so much Aljoscha. > > > > From: Aljoscha Krettek <aljos...@apache.org> > To: dev@flink.apache.org; amir bahmanyari <amirto...@yahoo.com> > Sent: Tuesday, April 4, 2017 1:59 AM > Subject: Re: Flink limitations under Beam > > Hi, > I think you would mainly lose on performance, since Beam adds an additional > layer of abstraction and has some requirements from Runners that slow things > down compared to running natively on Flink. > > I think feature wise, the only thing that you will lose is support for > Iterations/feedback edges. Flink has this while Beam does not (yet) have an > API for that. > > Best, > Aljoscha > > > On 4. Apr 2017, at 02:11, amir bahmanyari <amirto...@yahoo.com.INVALID > > <mailto:amirto...@yahoo.com.INVALID>> wrote: > > > > Hi colleagues, been a long time. New project.What feature(s)/capabilities > > of Flink would become unavailable/limited if the pipeline app is written in > > Beam sdk using FlinkRunner? > > Thanks+regards > >
