morningman opened a new pull request #2632: [Rowset Reader] Improve the merge 
read efficiency of alpha rowsets
URL: https://github.com/apache/incubator-doris/pull/2632
 
 
   When merge reads from multi rowsets, or one rowset with multi overlapping 
segments, 
   I introduce a priority queue(A Minimum heap data structure) for multipath 
merge sort, 
   to replace the old O(N^2) time complexity algorithm.
   
   This can significantly improve the read efficiency when merging large number 
of 
   overlapping data.
   
   In mytest:
   1. Compaction with 187 segments reduce time from 75 seconds to 42 seconds
   2. Compaction with 3574 segments cost 43 seconds, and with old version, I 
kill the 
   process after waiting more than 10 minutes...
   
   This CL only change the reads of alpha rowset. Beta rowset will be changed 
in another CL.
   
   ISSUE: #2631 

----------------------------------------------------------------
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:
[email protected]


With regards,
Apache Git Services

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

Reply via email to