You are viewing a plain text version of this content. The canonical link for it is here.

Posted to issues@kudu.apache.org by "Todd Lipcon (JIRA)" <ji...@apache.org> on 2018/03/27 16:39:00 UTC

[jira] [Created] (KUDU-2381) Optimize DeltaMemStore for case of no matching deltas

Todd Lipcon created KUDU-2381:
---------------------------------

             Summary: Optimize DeltaMemStore for case of no matching deltas
                 Key: KUDU-2381
                 URL: https://issues.apache.org/jira/browse/KUDU-2381
             Project: Kudu
          Issue Type: Improvement
          Components: perf, tablet
            Reporter: Todd Lipcon
            Assignee: Todd Lipcon


Currently in a scan workload which scans 280 columns I see DeltaMemStore iteration taking up a significant amount of CPU in the scan, despite the fact that the dataset has no updates. Of 1.6sec in MaterializingIterator::NextBlock, we spent 0.61s in DMSIterator::PrepareBatch and 0.14s in DMSIterator::MayHaveDeltas. So, about 46% of our time here is on wasted work.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)