taskmanager.cpu.cores 1.7976931348623157E308

[Rex Fenley]

Hello,

I'm tuning flink for parallelism right now and when I look at the JobManager I see

taskmanager.cpu.cores

1.7976931348623157E308

Which looks like the maximum double number.

We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.

Here is our configuration

"vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"

We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.

How do we correctly adjust this?

Thanks!

--

[Rex Fenley]

We're running this in a local environment so that may be contributing to what we're seeing.

On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:

Hello,

I'm tuning flink for parallelism right now and when I look at the JobManager I see

taskmanager.cpu.cores

1.7976931348623157E308

Which looks like the maximum double number.

We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.

Here is our configuration

"vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"

We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.

How do we correctly adjust this?

Thanks!

--

Rex Fenley  |  Software Engineer - Mobile and Backend

Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

--

[David Anderson-4]

taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?

Regards,

David

 

On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:

We're running this in a local environment so that may be contributing to what we're seeing.

On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:

Hello,

I'm tuning flink for parallelism right now and when I look at the JobManager I see

taskmanager.cpu.cores

1.7976931348623157E308

Which looks like the maximum double number.

We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.

Here is our configuration

"vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"

We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.

How do we correctly adjust this?

Thanks!

--

Rex Fenley  |  Software Engineer - Mobile and Backend

Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

--

Rex Fenley  |  Software Engineer - Mobile and Backend

Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Yangze Guo]

Hi, Rex,

Can you share more logs for it. Did you see something like "The
configuration option taskmanager.cpu.cores required for local
execution is not set, setting it to" in your logs?

Best,
Yangze Guo

Best,
Yangze Guo


On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:

>
> taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
>
> Regards,
> David
>
>
> On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
>>
>> We're running this in a local environment so that may be contributing to what we're seeing.
>>
>> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
>>>
>>> Hello,
>>>
>>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
>>> taskmanager.cpu.cores1.7976931348623157E308
>>> Which looks like the maximum double number.
>>>
>>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
>>>
>>> Here is our configuration
>>>
>>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
>>>
>>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
>>>
>>> How do we correctly adjust this?
>>>
>>> Thanks!
>>> --
>>>
>>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>>
>>>
>>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
>>
>>
>>
>> --
>>
>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>
>>
>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Yangze Guo]

My gut feeling is your "vmArgs" does not take effect.

Best,
Yangze Guo

On Mon, Dec 7, 2020 at 10:32 AM Yangze Guo <[hidden email]> wrote:

>
> Hi, Rex,
>
> Can you share more logs for it. Did you see something like "The
> configuration option taskmanager.cpu.cores required for local
> execution is not set, setting it to" in your logs?
>
> Best,
> Yangze Guo
>
> Best,
> Yangze Guo
>
>
> On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:
> >
> > taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
> >
> > Regards,
> > David
> >
> >
> > On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
> >>
> >> We're running this in a local environment so that may be contributing to what we're seeing.
> >>
> >> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
> >>>
> >>> Hello,
> >>>
> >>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
> >>> taskmanager.cpu.cores1.7976931348623157E308
> >>> Which looks like the maximum double number.
> >>>
> >>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
> >>>
> >>> Here is our configuration
> >>>
> >>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
> >>>
> >>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
> >>>
> >>> How do we correctly adjust this?
> >>>
> >>> Thanks!
> >>> --
> >>>
> >>> Rex Fenley  |  Software Engineer - Mobile and Backend
> >>>
> >>>
> >>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
> >>
> >>
> >>
> >> --
> >>
> >> Rex Fenley  |  Software Engineer - Mobile and Backend
> >>
> >>
> >> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Xintong Song]

Hi Rex,

We're running this in a local environment so that may be contributing to what we're seeing.

Just to double check on this. By `local environment`, you mean running flink without setting up a standalone cluster or submitting it to a K8s/Yarn cluster? (Typically executing from an IDE, running `flink run -t local`, or running your own application that calls `ExecutionEnvironment#execute`).

If yes, then this is kind of expected.

A couple of things that might help you understand this.

• Running on a local environment means setting up the Flink cluster within the current process (the IDE process if executed from an IDE, the flink client process if using `flink run -t local`, or your own application process). That also means most of the resource configurations cannot take effect, because the resources of the JVM are already determined. Please refer to the memory configuration documents for options that still take effect in local execution. [1][2]
• David is correct that `taskmanager.cpu.cores` is only intended for internal usages. I assume you learnt about this configuration by reading the source codes? If true, please also be aware that the JavaDoc of `TaskManagerOption#CPU_CORES` says "DO NOT USE THIS CONFIG OPTION", and it is also annotated with `ExcludeFromDocumentation` so that users do not learn this option from the documents.
• Flink does not really control how many cpu cores it uses. However, when running on an external resource management system (K8s, Yarn, Mesos), it requires a certain amount of cpu resources for its containers/pods, and allows the external system to control its cpu usage. You can use the following configuration options to control how many cpu cores are requested in such cases.
• kubernetes.jobmanager.cpu
  
• kubernetes.taskmanager.cpu
  
• yarn.appmaster.vcores
  
• yarn.containers.vcores
  
• mesos.resourcemanager.tasks.cpus
  

[1] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_tm.html#local-execution

[2] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_jobmanager.html#local-execution

On Mon, Dec 7, 2020 at 10:32 AM Yangze Guo <[hidden email]> wrote:

Hi, Rex,

Can you share more logs for it. Did you see something like "The
configuration option taskmanager.cpu.cores required for local
execution is not set, setting it to" in your logs?

Best,
Yangze Guo

Best,
Yangze Guo


On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:
>
> taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
>
> Regards,
> David
>
>
> On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
>>
>> We're running this in a local environment so that may be contributing to what we're seeing.
>>
>> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
>>>
>>> Hello,
>>>
>>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
>>> taskmanager.cpu.cores1.7976931348623157E308
>>> Which looks like the maximum double number.
>>>
>>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
>>>
>>> Here is our configuration
>>>
>>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
>>>
>>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
>>>
>>> How do we correctly adjust this?
>>>
>>> Thanks!
>>> --
>>>
>>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>>
>>>
>>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
>>
>>
>>
>> --
>>
>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>
>>
>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Xintong Song]

On Mon, Dec 7, 2020 at 11:03 AM Xintong Song <[hidden email]> wrote:

Hi Rex,

We're running this in a local environment so that may be contributing to what we're seeing.

Just to double check on this. By `local environment`, you mean running flink without setting up a standalone cluster or submitting it to a K8s/Yarn cluster? (Typically executing from an IDE, running `flink run -t local`, or running your own application that calls `ExecutionEnvironment#execute`).

If yes, then this is kind of expected.

A couple of things that might help you understand this.

• Running on a local environment means setting up the Flink cluster within the current process (the IDE process if executed from an IDE, the flink client process if using `flink run -t local`, or your own application process). That also means most of the resource configurations cannot take effect, because the resources of the JVM are already determined. Please refer to the memory configuration documents for options that still take effect in local execution. [1][2]
• David is correct that `taskmanager.cpu.cores` is only intended for internal usages. I assume you learnt about this configuration by reading the source codes? If true, please also be aware that the JavaDoc of `TaskManagerOption#CPU_CORES` says "DO NOT USE THIS CONFIG OPTION", and it is also annotated with `ExcludeFromDocumentation` so that users do not learn this option from the documents.
• Flink does not really control how many cpu cores it uses. However, when running on an external resource management system (K8s, Yarn, Mesos), it requires a certain amount of cpu resources for its containers/pods, and allows the external system to control its cpu usage. You can use the following configuration options to control how many cpu cores are requested in such cases.
• kubernetes.jobmanager.cpu
  
• kubernetes.taskmanager.cpu
  
• yarn.appmaster.vcores
  
• yarn.containers.vcores
  
• mesos.resourcemanager.tasks.cpus
  

Thank you~

Xintong Song

[1] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_tm.html#local-execution

[2] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_jobmanager.html#local-execution

On Mon, Dec 7, 2020 at 10:32 AM Yangze Guo <[hidden email]> wrote:

Hi, Rex,

Can you share more logs for it. Did you see something like "The
configuration option taskmanager.cpu.cores required for local
execution is not set, setting it to" in your logs?

Best,
Yangze Guo

Best,
Yangze Guo


On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:
>
> taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
>
> Regards,
> David
>
>
> On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
>>
>> We're running this in a local environment so that may be contributing to what we're seeing.
>>
>> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
>>>
>>> Hello,
>>>
>>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
>>> taskmanager.cpu.cores1.7976931348623157E308
>>> Which looks like the maximum double number.
>>>
>>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
>>>
>>> Here is our configuration
>>>
>>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
>>>
>>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
>>>
>>> How do we correctly adjust this?
>>>
>>> Thanks!
>>> --
>>>
>>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>>
>>>
>>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
>>
>>
>>
>> --
>>
>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>
>>
>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Xintong Song]

FYI, I've opened FLINK-20503 for this.

https://issues.apache.org/jira/browse/FLINK-20503

On Mon, Dec 7, 2020 at 11:10 AM Xintong Song <[hidden email]> wrote:

I forgot to mention that it is designed that task managers always have `Double#MAX_VALUE` cpu cores in local execution.

And I think Yangze is right. The log "The configuration option taskmanager.cpu.cores required for local execution is not set, setting it to" can be misleading for users. Will fire an issue on that.

Thank you~

Xintong Song

On Mon, Dec 7, 2020 at 11:03 AM Xintong Song <[hidden email]> wrote:

Hi Rex,

We're running this in a local environment so that may be contributing to what we're seeing.

Just to double check on this. By `local environment`, you mean running flink without setting up a standalone cluster or submitting it to a K8s/Yarn cluster? (Typically executing from an IDE, running `flink run -t local`, or running your own application that calls `ExecutionEnvironment#execute`).

If yes, then this is kind of expected.

A couple of things that might help you understand this.

• Running on a local environment means setting up the Flink cluster within the current process (the IDE process if executed from an IDE, the flink client process if using `flink run -t local`, or your own application process). That also means most of the resource configurations cannot take effect, because the resources of the JVM are already determined. Please refer to the memory configuration documents for options that still take effect in local execution. [1][2]
• David is correct that `taskmanager.cpu.cores` is only intended for internal usages. I assume you learnt about this configuration by reading the source codes? If true, please also be aware that the JavaDoc of `TaskManagerOption#CPU_CORES` says "DO NOT USE THIS CONFIG OPTION", and it is also annotated with `ExcludeFromDocumentation` so that users do not learn this option from the documents.
• Flink does not really control how many cpu cores it uses. However, when running on an external resource management system (K8s, Yarn, Mesos), it requires a certain amount of cpu resources for its containers/pods, and allows the external system to control its cpu usage. You can use the following configuration options to control how many cpu cores are requested in such cases.
• kubernetes.jobmanager.cpu
  
• kubernetes.taskmanager.cpu
  
• yarn.appmaster.vcores
  
• yarn.containers.vcores
  
• mesos.resourcemanager.tasks.cpus
  

Thank you~

Xintong Song

[1] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_tm.html#local-execution

[2] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_jobmanager.html#local-execution

On Mon, Dec 7, 2020 at 10:32 AM Yangze Guo <[hidden email]> wrote:

Hi, Rex,

Can you share more logs for it. Did you see something like "The
configuration option taskmanager.cpu.cores required for local
execution is not set, setting it to" in your logs?

Best,
Yangze Guo

Best,
Yangze Guo


On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:
>
> taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
>
> Regards,
> David
>
>
> On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
>>
>> We're running this in a local environment so that may be contributing to what we're seeing.
>>
>> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
>>>
>>> Hello,
>>>
>>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
>>> taskmanager.cpu.cores1.7976931348623157E308
>>> Which looks like the maximum double number.
>>>
>>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
>>>
>>> Here is our configuration
>>>
>>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
>>>
>>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
>>>
>>> How do we correctly adjust this?
>>>
>>> Thanks!
>>> --
>>>
>>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>>
>>>
>>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
>>
>>
>>
>> --
>>
>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>
>>
>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

[Rex Fenley]

Thanks for all this feedback, this is really helpful!

On Sun, Dec 6, 2020 at 7:23 PM Xintong Song <[hidden email]> wrote:

FYI, I've opened FLINK-20503 for this.

https://issues.apache.org/jira/browse/FLINK-20503

Thank you~

Xintong Song

On Mon, Dec 7, 2020 at 11:10 AM Xintong Song <[hidden email]> wrote:

I forgot to mention that it is designed that task managers always have `Double#MAX_VALUE` cpu cores in local execution.

And I think Yangze is right. The log "The configuration option taskmanager.cpu.cores required for local execution is not set, setting it to" can be misleading for users. Will fire an issue on that.

Thank you~

Xintong Song

On Mon, Dec 7, 2020 at 11:03 AM Xintong Song <[hidden email]> wrote:

Hi Rex,

We're running this in a local environment so that may be contributing to what we're seeing.

Just to double check on this. By `local environment`, you mean running flink without setting up a standalone cluster or submitting it to a K8s/Yarn cluster? (Typically executing from an IDE, running `flink run -t local`, or running your own application that calls `ExecutionEnvironment#execute`).

If yes, then this is kind of expected.

A couple of things that might help you understand this.

• Running on a local environment means setting up the Flink cluster within the current process (the IDE process if executed from an IDE, the flink client process if using `flink run -t local`, or your own application process). That also means most of the resource configurations cannot take effect, because the resources of the JVM are already determined. Please refer to the memory configuration documents for options that still take effect in local execution. [1][2]
• David is correct that `taskmanager.cpu.cores` is only intended for internal usages. I assume you learnt about this configuration by reading the source codes? If true, please also be aware that the JavaDoc of `TaskManagerOption#CPU_CORES` says "DO NOT USE THIS CONFIG OPTION", and it is also annotated with `ExcludeFromDocumentation` so that users do not learn this option from the documents.
• Flink does not really control how many cpu cores it uses. However, when running on an external resource management system (K8s, Yarn, Mesos), it requires a certain amount of cpu resources for its containers/pods, and allows the external system to control its cpu usage. You can use the following configuration options to control how many cpu cores are requested in such cases.
• kubernetes.jobmanager.cpu
  
• kubernetes.taskmanager.cpu
  
• yarn.appmaster.vcores
  
• yarn.containers.vcores
  
• mesos.resourcemanager.tasks.cpus
  

Thank you~

Xintong Song

[1] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_tm.html#local-execution

[2] https://ci.apache.org/projects/flink/flink-docs-release-1.11/ops/memory/mem_setup_jobmanager.html#local-execution

On Mon, Dec 7, 2020 at 10:32 AM Yangze Guo <[hidden email]> wrote:

Hi, Rex,

Can you share more logs for it. Did you see something like "The
configuration option taskmanager.cpu.cores required for local
execution is not set, setting it to" in your logs?

Best,
Yangze Guo

Best,
Yangze Guo


On Sat, Dec 5, 2020 at 6:53 PM David Anderson <[hidden email]> wrote:
>
> taskmanager.cpu.cores is intended for internal use only -- you aren't meant to set this option. What happens if you leave it alone?
>
> Regards,
> David
>
>
> On Sat, Dec 5, 2020 at 8:04 AM Rex Fenley <[hidden email]> wrote:
>>
>> We're running this in a local environment so that may be contributing to what we're seeing.
>>
>> On Fri, Dec 4, 2020 at 10:41 PM Rex Fenley <[hidden email]> wrote:
>>>
>>> Hello,
>>>
>>> I'm tuning flink for parallelism right now and when I look at the JobManager I see
>>> taskmanager.cpu.cores1.7976931348623157E308
>>> Which looks like the maximum double number.
>>>
>>> We have 8 cpu cores, so we figured we'd bump to 16 for hyper threading. We have 37 operators so we rounded up and set 40 task slots.
>>>
>>> Here is our configuration
>>>
>>> "vmArgs": "-Xmx16g -Xms16g -XX:MaxDirectMemorySize=1207959552 -XX:MaxMetaspaceSize=268435456 -Dlog.file=/tmp/flink.log -Dtaskmanager.memory.framework.off-heap.size=134217728b -Dtaskmanager.memory.network.max=1073741824b -Dtaskmanager.memory.network.min=1073741824b -Dtaskmanager.memory.framework.heap.size=134217728b -Dtaskmanager.memory.managed.size=6335076856b -Dtaskmanager.memory.task.heap.size=8160437768b -Dtaskmanager.memory.task.off-heap.size=0b -Dtaskmanager.numberOfTaskSlots=40 -Dtaskmanager.cpu.cores=16.0"
>>>
>>> We then tried with -Dtaskmanager.cpu.cores=7.0 and still ended up with that very odd value for cpu cores.
>>>
>>> How do we correctly adjust this?
>>>
>>> Thanks!
>>> --
>>>
>>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>>
>>>
>>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US
>>
>>
>>
>> --
>>
>> Rex Fenley  |  Software Engineer - Mobile and Backend
>>
>>
>> Remind.com |  BLOG  |  FOLLOW US  |  LIKE US

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