wgtmac commented on code in PR #55449:
URL: https://github.com/apache/arrow/pull/55449#discussion_r4526846027


##########
cpp/src/arrow/util/alp/alp_compression.cc:
##########


Review Comment:
   There is a related discussion at 
https://github.com/apache/arrow/pull/48345#discussion_r3144847232.
   
   The ALP paper uses early exit with at most 5 candidates and early exit 
threshold of 2. Our values are 5 and 4 respectively, so we cannot actually skip 
any candidates.
   
   Increasing the candidate count or lowering the threshold could make it 
useful, but the greedy search may miss a better candidate and hurt compression 
ratio. In the future, we can turn these sampling constants to configurable 
options to make them work.



-- 
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]

Reply via email to