Hi Prasanna, overcommitting cores was actually a recommended technique a while ago to counter-balance I/O. So it's not bad per se.
However, with slot sharing each core is already doing the work for source, transform, sink, so it's not necessary. So I'd go with slots = cores and I rather strongly suggest to switch to async I/O to perform the external transformation. [1] [1] https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/asyncio.html On Mon, Jul 6, 2020 at 7:01 PM Prasanna kumar <prasannakumarram...@gmail.com> wrote: > Hi , > > I used t2.medium machines for the task manager nodes. It has 2 CPU and 4GB > memory. > > But the task manager screen shows that there are 4 slots. > > Generally we should match the number of slots to the number of cores. > > [image: image.png] > > Our pipeline is Source -> Simple Transform -> Sink. > > What happens when we have more slots than cores in following scenarios? > 1) The transform is just changing of json format. > > 2) When the transformation is done by hitting another server (HTTP > request) > > Thanks, > Prasanna. > -- Arvid Heise | Senior Java Developer <https://www.ververica.com/> Follow us @VervericaData -- Join Flink Forward <https://flink-forward.org/> - The Apache Flink Conference Stream Processing | Event Driven | Real Time -- Ververica GmbH | Invalidenstrasse 115, 10115 Berlin, Germany -- Ververica GmbH Registered at Amtsgericht Charlottenburg: HRB 158244 B Managing Directors: Timothy Alexander Steinert, Yip Park Tung Jason, Ji (Toni) Cheng
