Hi Piper,

The repro is pretty simple:

  *   Submit a job with parallelism set higher than YARN has resources to 
support

What this ends up looking like in the Flink UI is this:
[cid:[email protected]]

The Job is in a “RUNNING” state, but all of the tasks are in the “SCHEDULED” 
state. The `jobmanager.numRunningJobs` metric that Flink emits by default will 
increase by 1, but none of the tasks actually get scheduled on any TM.

[cid:[email protected]]

What I’m looking for is a way to detect when I am in this state using Flink 
metrics (ideally the count of tasks in each state for better observability).

Does that make sense?

Thanks,
Kelly

From: Piper Piper <[email protected]>
Date: Thursday, November 21, 2019 at 12:59 PM
To: Kelly Smith <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: Metrics for Task States

Hello Kelly,

I thought that Flink scheduler only starts a job if all requested 
containers/TMs are available and allotted to that job.

How can I reproduce your issue on Flink with YARN?

Thank you,

Piper


On Thu, Nov 21, 2019, 1:48 PM Kelly Smith 
<[email protected]<mailto:[email protected]>> wrote:
I’ve been running Flink in production on EMR (YARN) for some time and have 
found the metrics system to be quite useful, but there is one specific case 
where I’m missing a signal for this scenario:


  *   When a job has been submitted, but YARN does not have enough resources to 
provide

Observed:

  *   Job is in RUNNING state
  *   All of the tasks for the job are in the (I believe) DEPLOYING state

Is there a way to access these as metrics for monitoring the number of tasks in 
each state for a given job (image below)? The metric I’m currently using is the 
number of running jobs, but it misses this “unhealthy” scenario. I realize that 
I could use application-level metrics (record counts, etc) as a proxy for this, 
but I’m working on providing a streaming platform and need all of my monitoring 
to be application agnostic.
[cid:[email protected]]

I can’t find anything on it in the documentation.

Thanks,
Kelly

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