Spark on YARN not utilizing all the YARN containers available

[kant kodali]

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Dillon Dukek]

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Gourav Sengupta]

hi,

may be I am not quite clear in my head on this one. But how do we know that 1 yarn container = 1 executor?

Regards,

Gourav Sengupta

On Tue, Oct 9, 2018 at 8:53 PM Dillon Dukek <[hidden email]> wrote:

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Dillon Dukek]

I'm still not sure exactly what you are meaning by saying that you have 6 yarn containers. Yarn should just be aware of the total available resources in  your cluster and then be able to launch containers based on the executor requirements you set when you submit your job. If you can, I think it would be helpful to send me the command you're using to launch your spark process. You should also be able to use the logs and/or the spark UI to determine how many executors are running.

On Tue, Oct 9, 2018 at 12:57 PM Gourav Sengupta <[hidden email]> wrote:

hi,

may be I am not quite clear in my head on this one. But how do we know that 1 yarn container = 1 executor?

Regards,

Gourav Sengupta

On Tue, Oct 9, 2018 at 8:53 PM Dillon Dukek <[hidden email]> wrote:

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Gourav Sengupta]

Hi Dillon,

I do think that there is a setting available where in once YARN sets up the containers then you do not deallocate them, I had used it previously in HIVE, and it just saves processing time in terms of allocating containers. That said I am still trying to understand how do we determine one YARN container = one executor in SPARK.

Regards,

Gourav

On Tue, Oct 9, 2018 at 9:04 PM Dillon Dukek <[hidden email]> wrote:

I'm still not sure exactly what you are meaning by saying that you have 6 yarn containers. Yarn should just be aware of the total available resources in  your cluster and then be able to launch containers based on the executor requirements you set when you submit your job. If you can, I think it would be helpful to send me the command you're using to launch your spark process. You should also be able to use the logs and/or the spark UI to determine how many executors are running.

On Tue, Oct 9, 2018 at 12:57 PM Gourav Sengupta <[hidden email]> wrote:

hi,

may be I am not quite clear in my head on this one. But how do we know that 1 yarn container = 1 executor?

Regards,

Gourav Sengupta

On Tue, Oct 9, 2018 at 8:53 PM Dillon Dukek <[hidden email]> wrote:

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Dillon Dukek]

There is documentation here http://spark.apache.org/docs/latest/running-on-yarn.html about running spark on YARN. Like I said before you can use either the logs from the application or the Spark UI to understand how many executors are running at any given time. I don't think I can help much further without more information about the specific use case.

On Tue, Oct 9, 2018 at 2:54 PM Gourav Sengupta <[hidden email]> wrote:

Hi Dillon,

I do think that there is a setting available where in once YARN sets up the containers then you do not deallocate them, I had used it previously in HIVE, and it just saves processing time in terms of allocating containers. That said I am still trying to understand how do we determine one YARN container = one executor in SPARK.

Regards,

Gourav

On Tue, Oct 9, 2018 at 9:04 PM Dillon Dukek <[hidden email]> wrote:

I'm still not sure exactly what you are meaning by saying that you have 6 yarn containers. Yarn should just be aware of the total available resources in  your cluster and then be able to launch containers based on the executor requirements you set when you submit your job. If you can, I think it would be helpful to send me the command you're using to launch your spark process. You should also be able to use the logs and/or the spark UI to determine how many executors are running.

On Tue, Oct 9, 2018 at 12:57 PM Gourav Sengupta <[hidden email]> wrote:

hi,

may be I am not quite clear in my head on this one. But how do we know that 1 yarn container = 1 executor?

Regards,

Gourav Sengupta

On Tue, Oct 9, 2018 at 8:53 PM Dillon Dukek <[hidden email]> wrote:

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks! 

[Gourav Sengupta]

Hi Dillon,

yes we can understand the number of executors that are running but the question is more around understanding the relation between YARN containers, their persistence and SPARK excutors.

Regards,

Gourav 

On Wed, Oct 10, 2018 at 6:38 AM Dillon Dukek <[hidden email]> wrote:

There is documentation here http://spark.apache.org/docs/latest/running-on-yarn.html about running spark on YARN. Like I said before you can use either the logs from the application or the Spark UI to understand how many executors are running at any given time. I don't think I can help much further without more information about the specific use case.

On Tue, Oct 9, 2018 at 2:54 PM Gourav Sengupta <[hidden email]> wrote:

Hi Dillon,

I do think that there is a setting available where in once YARN sets up the containers then you do not deallocate them, I had used it previously in HIVE, and it just saves processing time in terms of allocating containers. That said I am still trying to understand how do we determine one YARN container = one executor in SPARK.

Regards,

Gourav

On Tue, Oct 9, 2018 at 9:04 PM Dillon Dukek <[hidden email]> wrote:

I'm still not sure exactly what you are meaning by saying that you have 6 yarn containers. Yarn should just be aware of the total available resources in  your cluster and then be able to launch containers based on the executor requirements you set when you submit your job. If you can, I think it would be helpful to send me the command you're using to launch your spark process. You should also be able to use the logs and/or the spark UI to determine how many executors are running.

On Tue, Oct 9, 2018 at 12:57 PM Gourav Sengupta <[hidden email]> wrote:

hi,

may be I am not quite clear in my head on this one. But how do we know that 1 yarn container = 1 executor?

Regards,

Gourav Sengupta

On Tue, Oct 9, 2018 at 8:53 PM Dillon Dukek <[hidden email]> wrote:

Can you send how you are launching your streaming process? Also what environment is this cluster running in (EMR, GCP, self managed, etc)?

On Tue, Oct 9, 2018 at 10:21 AM kant kodali <[hidden email]> wrote:

Hi All,

I am using Spark 2.3.1 and using YARN as a cluster manager.

I currently got

1) 6 YARN containers(executors=6) with 4 executor cores for each container. 

2) 6 Kafka partitions from one topic.

3) You can assume every other configuration is set to whatever the default values are.

Spawned a Simple Streaming Query and I see all the tasks get scheduled on one YARN container. am I missing any config?

Thanks!