[
https://issues.apache.org/jira/browse/CALCITE-3851?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17059399#comment-17059399
]
Haisheng Yuan commented on CALCITE-3851:
----------------------------------------
{{String}} is immutable, but it has mutable field {{hash}}, once {{hash}} is
set, it can't be changed again. The {{pruned}} field of {{AbstractRelNode}}
serves the same purpose of {{String.hash}}. {{pruned}} can also be its own
state of {{RelNode}}. Once it is pruned, it can't be un-pruned. It doesn't
needs to planner state. Pruned relnode should not passed across different
planner, otherwise, it is planner's bug, some pruned relnode is still used.
> Replace the node importance map with a set for pruned nodes
> -----------------------------------------------------------
>
> Key: CALCITE-3851
> URL: https://issues.apache.org/jira/browse/CALCITE-3851
> Project: Calcite
> Issue Type: Improvement
> Components: core
> Reporter: Liya Fan
> Priority: Minor
> Labels: pull-request-available
> Time Spent: 1h 40m
> Remaining Estimate: 0h
>
> Currently, volcano planner stores rel node importances with a map. In fact,
> the value of the map can only be 0.
> So there is no need to store the values, and we replace the map with a set to
> store nodes whose importances are 0.
> This makes the code logic clearer, and avoids instability caused by comparing
> floating point values.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
