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
>>>
>>>
>>

Reply via email to