gianm commented on issue #19344:
URL: https://github.com/apache/druid/issues/19344#issuecomment-4266616139

   I guess "TopN Ranking (24h)" is the one you're worried about? The other 
cases seem to be the same or faster in Druid 37 (on JDK 21) vs Druid 27.
   
   The TopN case is likely suffering from not being vectorized. (None of the 
`topN` query algorithms are currently vectorized.) With numeric vector 
selectors (`VectorValueSelector`) there is a `getNullVector` method that is 
called once per row batch, and returns `null` itself to indicate that no nulls 
exist in the batch. The vectorized query engines take advantage of that to skip 
null handling for the entire batch. So, vectorizing topN would be very helpful 
for this one.


-- 
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.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]


---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to