lyso opened a new pull request, #29602:
URL: https://github.com/apache/airflow/pull/29602

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   This PR changes the default value for configure 
``scheduler.max_tis_per_query`` to 16 and update related document.
   
   Before this change `scheduler.max_tis_per_query=512` by default. 
   
   ``scheduler.max_tis_per_query`` should not be greater than 
``core.parallelism`` according to related code 
[[1]](https://github.com/apache/airflow/blob/49867b660b6231c1319969217bc61917f7cf9829/airflow/jobs/scheduler_job.py#L581)
 and 
[[2]](https://github.com/apache/airflow/blob/49867b660b6231c1319969217bc61917f7cf9829/airflow/executors/base_executor.py#L331).
 If both configurations use default value, the default 512 of 
`max_tis_per_query` is never used.
   
   After this PR, default will set ``scheduler.max_tis_per_query=16`` and 
``core.parallelism=32``. This will make the executor can be populated in two 
iteration of scheduler main loop.
   
   The actual change applied in Airflow runtime by this PR is to reduce the 
``max_tis`` from 32 to 16. The query batch size reduced. This can help 
scheduler finish the iteration faster. Thus make scheduler more responsive and 
healthy. 
   
   This PR also updated related document about ``scheduler.max_tis_per_query`` 
to help users understand how to set this configuration.
   
   
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