gianm commented on issue #19456:
URL: https://github.com/apache/druid/issues/19456#issuecomment-4486406707

   > Another thing I want to call out here is starting to move towards 
deprecating and unifying the available engines in Druid. Currently I see a lot 
of work being done on various engines (dart, msq, native, etc.) and what I 
think we should be aiming towards is the native processing core to be built out 
on whatever the decided "next" gen engine is (and its operator interfaces).
   
   This is another reason I mentioned a nudge towards MSQ. In addition to 
having a Frame concept that should be relatively straightforward to swap out 
for an Arrow batch, it is also a generally more capable engine and one that I 
expect we'll standardize on in time.
   
   Fwiw, MSQ and Dart are the same underlying engine. Really MSQ is the engine 
and Dart is a "profile" of the engine. It is a mode where the Broker runs query 
controllers and the Historicals are query workers. The other MSQ profile is 
Tasks, where the controllers and workers are all launched as tasks.
   
   Anyway, I think a lot of interesting experiments could be done without 
necessarily needing to get into the leaf processing stuff. For example, the MSQ 
`sortMergeJoin` implementation operates purely on Frames and could be swapped 
out for something else. The MSQ `groupBy` implementation has a per-segment 
partial-aggregation phase that emits Frames, followed by a phase that sorts 
those Frames, followed by a merge of sorted streams of Frames. Another 
experiment there could keep the per-segment partial-aggregation stuff as-is, 
and swap out the sort-to-sort-merge part with some other form of aggregation 
operation.


-- 
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