Hi Cam,

If you set parallelism to 60, then you would make use of all 60 slots you
have and
for you case, each slot executes a chained operator contains 13 tasks. It
is not
the case one slot executes at least 60 sub-tasks.

Best,
tison.


Cam Mach <cammac...@gmail.com> 于2019年8月12日周一 下午7:55写道:

> Hi Zhu and Abhishek,
>
> Thanks for your response and pointers. It's correct, the count of
> parallelism will be the number of slot used for a pipeline. And, the number
> (or count) of the parallelism is also used to generate number of sub-tasks
> for each operator. In my case, I have parallelism of 60, it generates 60
> sub-tasks for each operator. And so it'll be too much for one slot execute
> at least 60 sub-tasks. I am wondering if there is a way we can set number
> of generated sub-tasks, different than number of parallelism?
>
> Cam Mach
> Software Engineer
> E-mail: cammac...@gmail.com
> Tel: 206 972 2768
>
>
>
> On Sun, Aug 11, 2019 at 10:37 PM Zhu Zhu <reed...@gmail.com> wrote:
>
>> Hi Cam,
>> This case is expected due to slot sharing.
>> A slot can be shared by one instance of different tasks. So the used slot
>> is count of your max parallelism of a task.
>> You can specify the shared group with slotSharingGroup(String
>> slotSharingGroup) on operators.
>>
>> Thanks,
>> Zhu Zhu
>>
>> Abhishek Jain <abhijai...@gmail.com> 于2019年8月12日周一 下午1:23写道:
>>
>>> What you'se seeing is likely operator chaining. This is the default
>>> behaviour of grouping sub tasks to avoid transer overhead (from one slot to
>>> another). You can disable chaining if you need to. Please refer task
>>> and operator chains
>>> <https://ci.apache.org/projects/flink/flink-docs-stable/concepts/runtime.html#tasks-and-operator-chains>
>>> .
>>>
>>> - Abhishek
>>>
>>> On Mon, 12 Aug 2019 at 09:56, Cam Mach <cammac...@gmail.com> wrote:
>>>
>>>> Hello Flink expert,
>>>>
>>>> I have a cluster with 10 Task Managers, configured with 6 task slot
>>>> each, and a pipeline that has 13 tasks/operators with parallelism of 5. But
>>>> when running the pipeline I observer that only  5 slots are being used, the
>>>> other 55 slots are available/free. It should use all of my slots, right?
>>>> since I have 13 (tasks) x 5 = 65 sub-tasks? What are the configuration that
>>>> I missed in order to leverage all of the available slots for my pipelines?
>>>>
>>>> Thanks,
>>>> Cam
>>>>
>>>>
>>>

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