[CALCITE-3460] Poor performance in RexReplacer for large queries

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: core
• Labels: pull-request-available
• Assignee: Unassigned
• Reporter: Haisheng Yuan
• Created: 30/Oct/19 07:10
• Updated: 30/Apr/23 09:02

Description

We have queries that have tens of thousands of RexCalls. reducibleExps.indexOf(call) is an O 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.

Issue Links

• links to: GitHub Pull Request #1547