Are you running on the Dataflow runner? If so, Dataflow - unlike Spark and
Flink - dynamically modifies the parallelism as the operator runs, so there
is no need to have such controls. In fact these specific controls wouldn't
make much sense for the way Dataflow implements these operators.

On Sun, Apr 16, 2023 at 12:25 AM Jeff Zhang <zjf...@gmail.com> wrote:

> Just for performance tuning like in Spark and Flink.
>
>
> On Sun, Apr 16, 2023 at 1:10 PM Robert Bradshaw via user <
> user@beam.apache.org> wrote:
>
>> What are you trying to achieve by setting the parallelism?
>>
>> On Sat, Apr 15, 2023 at 5:13 PM Jeff Zhang <zjf...@gmail.com> wrote:
>>
>>> Thanks Reuven, what I mean is to set the parallelism in operator level.
>>> And the input size of the operator is unknown at compiling stage if it is
>>> not a source
>>>  operator,
>>>
>>> Here's an example of flink
>>> https://nightlies.apache.org/flink/flink-docs-master/docs/dev/datastream/execution/parallel/#operator-level
>>> Spark also support to set operator level parallelism (see groupByKey
>>> and reduceByKey):
>>> https://spark.apache.org/docs/latest/rdd-programming-guide.html
>>>
>>>
>>> On Sun, Apr 16, 2023 at 1:42 AM Reuven Lax via user <
>>> user@beam.apache.org> wrote:
>>>
>>>> The maximum parallelism is always determined by the parallelism of your
>>>> data. If you do a GroupByKey for example, the number of keys in your data
>>>> determines the maximum parallelism.
>>>>
>>>> Beyond the limitations in your data, it depends on your execution
>>>> engine. If you're using Dataflow, Dataflow is designed to automatically
>>>> determine the parallelism (e.g. work will be dynamically split and moved
>>>> around between workers, the number of workers will autoscale, etc.), so
>>>> there's no need to explicitly set the parallelism of the execution.
>>>>
>>>> On Sat, Apr 15, 2023 at 1:12 AM Jeff Zhang <zjf...@gmail.com> wrote:
>>>>
>>>>> Besides the global parallelism of beam job, is there any way to set
>>>>> parallelism for individual operators like group by and join? I
>>>>> understand the parallelism setting depends on the underlying execution
>>>>> engine, but it is very common to set parallelism like group by and join in
>>>>> both spark & flink.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Best Regards
>>>>>
>>>>> Jeff Zhang
>>>>>
>>>>
>>>
>>> --
>>> Best Regards
>>>
>>> Jeff Zhang
>>>
>>
>
> --
> Best Regards
>
> Jeff Zhang
>

Reply via email to