[jira] [Commented] (CALCITE-3460) Poor performance in RexReplacer for large queries

["Chunwei Lei (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CALCITE-3460?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16988390#comment-16988390 ] 

Chunwei Lei commented on CALCITE-3460:
--------------------------------------

Could you please add a test? We might get it into 1.22:).

> Poor performance in RexReplacer for large queries
> -------------------------------------------------
>
>                 Key: CALCITE-3460
>                 URL: https://issues.apache.org/jira/browse/CALCITE-3460
>             Project: Calcite
>          Issue Type: Improvement
>          Components: core
>            Reporter: Haisheng Yuan
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 2h 40m
>  Remaining Estimate: 0h
>
> We have queries that have tens of thousands of RexCalls. reducibleExps.indexOf(call) is an O(n) operation, which takes 50% of the running time, causing the query runs for ever until timed out.
> In RexShuttle, ImmutableList iterator creation in {{visitList}} takes another 5~7% of running time, and it is creating millions of temporary iterator object, not only time consuming, but also memory consuming.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)