Hi, This depends on the operator Z. If it has multiple input ports and those are optional, you can add P, then connect P to Z (and X), then remove Y.
If Z has a single port, then Z and everything downstream would need to be removed or else the change won't result in a valid DAG and won't be accepted. Thomas On Tue, Aug 30, 2016 at 1:48 PM, Hyunseok Chang <hyunseok.ch...@gmail.com> wrote: > So if I replace Y in pipeline X -> Y -> Z -> U -> W -> V with P, then what > I would have is X -> P -> Z' -> U' -> W' -> V' ? Where Z', U', W' and V' > are new operator instances that need to be deployed along with P. > > Is my understanding correct? If so is there any reason why we cannot > re-use existing operators downstream? > > -hs > > > On Tue, Aug 30, 2016 at 2:46 PM, Amol Kekre <a...@datatorrent.com> wrote: > >> >> Hyunseok, >> The new route in the pipeline will have a new Z operator. If you want to >> use the old Z operator (state?) then things get tricky. Do confirm that you >> do not plan to use old Z operator. >> >> Thks, >> Amol >> >> >> On Tue, Aug 30, 2016 at 11:02 AM, Sandesh Hegde <sand...@datatorrent.com> >> wrote: >> >>> Hello hs, >>> >>> Yes, you can change the topology from the Apex CLI. >>> >>> One possible sequence of commands for your scenario is described below, >>> >>> connect appid >>> begin-logical-plan-change >>> create-operator .... >>> add-stream-sink ... ( for the input of P ) >>> add-stream-sink ... ( for the output of P ) >>> remove-operator ... >>> submit >>> >>> Note: All the required operators needs to be in the package. >>> >>> Thanks >>> >>> >>> >>> >>> >>> On Tue, Aug 30, 2016 at 7:22 AM Hyunseok Chang <hyunseok.ch...@gmail.com> >>> wrote: >>> >>>> Hi, >>>> >>>> I'd like to know more about Apex support for dynamic topology. >>>> >>>> From my readings on Apex, I understand we can add additional parallel >>>> tasks for each operator and change data partitioning among them dynamically >>>> at run time (so-called data partitioning and unification features). >>>> >>>> My question is can we change the "logical" DAG at run time? >>>> >>>> Let's say my logical DAG is a chain of three operators X, Y & Z (i.e., >>>> X -> Y -> Z). Now at run time I want to replace operator Y with operator >>>> P, such that the new logical DAG would look like X -> P -> Z. >>>> >>>> Is it something I can do with Apex? >>>> >>>> Thanks! >>>> -hs >>>> >>>> >> >
