Thanks Caizhi, that was what I was afraid of. Thanks for the information on the 
REST API 😊

It seems like the right solution would be to add it as a first-class feature 
for Flink so I will add a feature request. I may end up using the REST API as a 
workaround in the short-term - probably with a side-car container once we move 
to Kubernetes.

Kelly

From: Caizhi Weng <tsreape...@gmail.com>
Date: Monday, November 25, 2019 at 1:41 AM
To: Kelly Smith <kell...@zillowgroup.com>
Cc: Piper Piper <piperfl...@gmail.com>, "user@flink.apache.org" 
<user@flink.apache.org>
Subject: Re: Metrics for Task States

Hi Kelly,

As far as I know Flink currently does not have such metrics to monitor on the 
number of tasks in each states. See 
https://ci.apache.org/projects/flink/flink-docs-stable/monitoring/metrics.html<https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fci.apache.org%2Fprojects%2Fflink%2Fflink-docs-stable%2Fmonitoring%2Fmetrics.html&data=02%7C01%7Ckellysm%40zillowgroup.com%7C2e123af242df4c2794b708d7718bb535%7C033464830d1840e7a5883784ac50e16f%7C0%7C0%7C637102717167008430&sdata=0P9tJLl7H5yjw4ov5Kkn2rwr4YDiOPCpU%2Fa%2BAeQeZhc%3D&reserved=0>
 for the complete metrics list. (It seems that `taskSlotsAvailable` in the 
metrics list is the most related metrics).

But Flink has a REST api which can provide states for all the tasks 
(http://hostname:port/overview). This REST returns a json string containing all 
the metrics you want. Maybe you can write your own tool to monitor on this api.

If you really want to have metrics that describe the number of tasks in each 
states, you can open up a JIRA ticket at 
https://issues.apache.org/jira/projects/FLINK/issues/<https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fissues.apache.org%2Fjira%2Fprojects%2FFLINK%2Fissues%2F&data=02%7C01%7Ckellysm%40zillowgroup.com%7C2e123af242df4c2794b708d7718bb535%7C033464830d1840e7a5883784ac50e16f%7C0%7C0%7C637102717167008430&sdata=0gR88PMtJmE9JE53grFTquRdFkKssd3YUG2oufPRe3U%3D&reserved=0>

Thank you

Kelly Smith <kell...@zillowgroup.com<mailto:kell...@zillowgroup.com>> 
于2019年11月25日周一 上午12:59写道:
With EMR/YARN, the cluster is definitely running in session mode. It exists 
independently of any job and continues running after the job exits.
Whether or not this is a bug in Flink, is it possible to get access to the 
metrics I'm asking about? Those would be useful even if this behavior is fixed.
Get Outlook for 
Android<https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Faka.ms%2Fghei36&data=02%7C01%7Ckellysm%40zillowgroup.com%7C2e123af242df4c2794b708d7718bb535%7C033464830d1840e7a5883784ac50e16f%7C0%7C0%7C637102717167018425&sdata=WIM9W5dCtpxc4HWa0Azf1SvO4TtUl7ZpCDkxMyfhw94%3D&reserved=0>

________________________________
From: Piper Piper <piperfl...@gmail.com<mailto:piperfl...@gmail.com>>
Sent: Friday, November 22, 2019 9:10:41 PM
To: Kelly Smith <kell...@zillowgroup.com<mailto:kell...@zillowgroup.com>>
Cc: user@flink.apache.org<mailto:user@flink.apache.org> 
<user@flink.apache.org<mailto:user@flink.apache.org>>
Subject: Re: Metrics for Task States

I am trying to reason why this problem should occur (i.e. why Flink could not 
reject the job when it required more slots than were available).

Flink in production on EMR (YARN): Does this mean Flink was being run in Job 
mode or Session mode?

Thank you,

Piper

On Thu, Nov 21, 2019 at 4:56 PM Piper Piper 
<piperfl...@gmail.com<mailto:piperfl...@gmail.com>> wrote:
Thank you, Kelly!

On Thu, Nov 21, 2019 at 4:06 PM Kelly Smith 
<kell...@zillowgroup.com<mailto:kell...@zillowgroup.com>> wrote:

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:16ea1e8b5784cff311]



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:16ea1e8b5785b16b22]



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 <piperfl...@gmail.com<mailto:piperfl...@gmail.com>>
Date: Thursday, November 21, 2019 at 12:59 PM
To: Kelly Smith <kell...@zillowgroup.com<mailto:kell...@zillowgroup.com>>
Cc: "user@flink.apache.org<mailto:user@flink.apache.org>" 
<user@flink.apache.org<mailto:user@flink.apache.org>>
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 
<kell...@zillowgroup.com<mailto:kell...@zillowgroup.com>> 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.

Error! Filename not specified.



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



Thanks,

Kelly

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