[SOLR-17299] Redesign debug component / reranking to support multi-stage debugging

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Chris M. Hostetter
• Created: 17/May/24 20:45
• Updated: 29/May/24 23:51

Description

It is currently not possible to get accurate debug=results (aka: explain) information when using the reRankScale option of query reanking in a distributed cloud request w/o using distrib.singlePass=true

This is because...

...in order to do proper explain for minMaxScaling you need to know the min and max score in the result set. This piece of state is maintained in the ReRankScaler itself which is inside of the ReRankQuery. But for this information to be populated the query must first be run. In distributed mode, explain is called in the second pass when the ids query is run so the state needed for the explain is not populated. ...

This ticket exists to track possible future work for improving the design of either the debug component, or the reranker, so that the necessary information can be communicated across multiple stages of a multi-stage distributed request

Issue Links

• split from: SOLR-17296 rerank w/scaling (still) broken when using debug to get explain info