Lars Volker created IMPALA-7731: ----------------------------------- Summary: Add ration between scanned and transmitted bytes to fragment instances Key: IMPALA-7731 URL: https://issues.apache.org/jira/browse/IMPALA-7731 Project: IMPALA Issue Type: Improvement Components: Backend Affects Versions: Impala 3.1.0 Reporter: Lars Volker Attachments: Selective Scan Slowdowns.png
Selective scans (and by extension selective fragment instances) take higher performance hits when reading data remotely. They can be identified by a low ratio between data being transmitted vs data being read from HDFS. To make it easier to spot those instances we should add this ratio to each instance and to the root of the execution profile. !Selective Scan Slowdowns.png! -- This message was sent by Atlassian JIRA (v7.6.3#76005)