jscheffl commented on PR #42410:
URL: https://github.com/apache/airflow/pull/42410#issuecomment-2453088900

   > > I don't see a point that there is a real "functional need" to set 
priorities exponential or in another manner that - with a normal modelling - yo 
need such large ranges
   > 
   > Let's not forget that we have the priority-weight cumulation: upstream, 
downstream and eventually Custom: 
https://airflow.apache.org/docs/apache-airflow/stable/administration-and-deployment/priority-weight.html#custom-weight-rule
   > 
   > I can quite easily imagine some big numbers when we have huge 1000s task 
dags with multiple upstream/downstream tasks (and layers) and especially with 
custom weights I can easily imagine those numbers to add up (or maybe multiply 
in custom rules if one wants to have more aggressive priority propagation).
   
   I still don't see a real need and use of such high numbers. Yes we 
accumulate priority weights by making sums. Assume we have a DAG with 1000 
tasks chained (I hope nobody is modelling this, will really run a long time) 
and we use a priority of 10k (=10000). Then the accumulated priority is at 10 
million.
   
   Looking into the INT value we use today the supported database have integer 
ranges with:
   
   - postgres: -2147483648 to +2147483647 (see 
https://www.postgresql.org/docs/current/datatype-numeric.html)
   - mysql: -2147483648 to +2147483647 (see 
https://dev.mysql.com/doc/refman/8.4/en/integer-types.html)
   - sqlite: -9223372036854775808 to +9223372036854775807 (see 
https://sqlite.org/datatype3.html)
   
   This means I still can have 1000 tasks with a priority of 1 million in my 
DAG. Which is also something in the range of values you can model to fit into 
the INT range.
   
   Instead of switching to float I think we should rather cap the values and 
ensure they can not roll-over. And add documentation about the limits. The 
limtis of postgres and mysql are the same and sound reasonable (else: there is 
also the option to switch to bigint of course if you want to support incredible 
numbers non-float).


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