Tim Armstrong created IMPALA-9317:
-------------------------------------
Summary: Improve number of instances estimate for scans in planner
Key: IMPALA-9317
URL: https://issues.apache.org/jira/browse/IMPALA-9317
Project: IMPALA
Issue Type: Improvement
Components: Frontend
Reporter: Tim Armstrong
Currently the number of instances (used for various estimates) is calculated as
estimated # hosts * mt_dop. This is suboptimal, because in many cases there
isn't enough input data to allow creating that many instances per host.
The per-host estimate for scans actually already handles this correctly by
capping the hosts estimate at the number of input splits - we should use the
same approach for number of instance estimates.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
