[GitHub] [spark] cloud-fan commented on issue #24223: [SPARK-27278][SQL] Optimize GetMapValue when the map is a foldable and the key is not

[GitBox <gi...@apache.org>]

cloud-fan commented on issue #24223: [SPARK-27278][SQL] Optimize GetMapValue when the map is a foldable and the key is not
URL: https://github.com/apache/spark/pull/24223#issuecomment-479477001
 
 
   IIUC this is kind of loop unrolling: `GetMapValue` looks up the map key via a while loop. `CaseKeyWhen` looks up the map key via a bunch of if-else.
   
   But unlimited look unrolling does hurt performance. Maybe we should introduce a config for the map size? I'm not sure how often we can hit this optimization. If it's rare, maybe we should simply revert it as it's not worth the complexity.

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org