Hi Kyle,

Thank you for the prompt response and apologize for the late reply. 

[1] seems to be only available in python portable_runner but not java 
PortableRunner, is it intended or we could add similar changes in java as well?

[2] makes sense to block since the wait/retry is handled in the previous 
prepare(), however, is there any specific reason why we do not want to support 
timeout in start worker request?

Best,
Ke

> On May 14, 2021, at 11:25 AM, Kyle Weaver <[email protected]> wrote:
> 
> 1. and 2. are both facilitated by GRPC, which takes care of most of the 
> retry/wait logic. In some places we have a configurable timeout (which 
> defaults to 60s) [1], while in other places we block [2][3].
> 
> [1] https://issues.apache.org/jira/browse/BEAM-7933 
> <https://issues.apache.org/jira/browse/BEAM-7933>
> [2] 
> https://github.com/apache/beam/blob/51541a595b09751dd3dde2c50caf2a968ac01b68/sdks/python/apache_beam/runners/portability/portable_runner.py#L238-L242
>  
> <https://github.com/apache/beam/blob/51541a595b09751dd3dde2c50caf2a968ac01b68/sdks/python/apache_beam/runners/portability/portable_runner.py#L238-L242>
> [3] 
> https://github.com/apache/beam/blob/9601bdef8870bc6acc7895c06252e43ec040bd8c/runners/java-fn-execution/src/main/java/org/apache/beam/runners/fnexecution/environment/ExternalEnvironmentFactory.java#L115
>  
> <https://github.com/apache/beam/blob/9601bdef8870bc6acc7895c06252e43ec040bd8c/runners/java-fn-execution/src/main/java/org/apache/beam/runners/fnexecution/environment/ExternalEnvironmentFactory.java#L115>
> On Fri, May 14, 2021 at 10:51 AM Ke Wu <[email protected] 
> <mailto:[email protected]>> wrote:
> Hello All,
> 
> I came across this question when I am reading Beam on Flink on Kubernetes 
> <https://docs.google.com/document/d/1z3LNrRtr8kkiFHonZ5JJM_L4NWNBBNcqRc_yAf6G0VI/edit#heading=h.x9qy4wlfgc1g>
>  and flink-on-k8s-operator 
> <https://github.com/GoogleCloudPlatform/flink-on-k8s-operator/tree/0310df76d6e2128cd5d2bc51fae4e842d370c463>
>  and realized that there seems no retry/wait logic built in PortableRunner 
> nor ExternalEnvironmentFactory, (correct me if I am wrong) which creates 
> implications that:
> 
> 1. Job Server needs to be ready to accept request before SDK Client could 
> submit request.
> 2. External Worker Pool Service needs to be ready to accept start/stop worker 
> request before runner starts to request.
> 
> This may bring some challenges on k8s since Flink opt to use multi containers 
> pattern when bringing up a beam portable pipeline, in addition, I don’t find 
> any special lifecycle management in place to guarantee the order, e.g. 
> External Worker Pool Service container to start and ready before the task 
> manager container to start making requests. 
> 
> I am wondering if I missed anything to guarantee the readiness of the 
> dependent service or we are relying on that dependent containers are much 
> lighter weigh so it should, in most time, be ready before the other container 
> start to make requests. 
> 
> Best,
> Ke
> 

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