[SOLR-14607] LTR Query, timeAllowed parameter causes a timeout exception with no result

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: master (9.0)
• Component/s: contrib - LTR
• Assignee: Unassigned
• Reporter: Dawn
• Created: 30/Jun/20 15:28
• Updated: 25/Jul/20 15:45

Description

When using the LTR, open timeAllowed parameter, LTR feature of query may call 'ExitableFilterAtomicReader.CheckAndThrow' timeout checks.

If a timeout occurs at this point, the exception ExitingReaderException is thrown, Lead to null result.

Exception information:

 The request took too long to iterate over terms. Timeout: timeoutAt: 50321611131050 (System.nanoTime(): 50321639573838), TermsEnum=org.apache.lucene.codecs.blocktree.SegmentTermsEnum@62eaeeaa

 

Can hold this exception in the LTR, returning partial results rather than null.

This exception occurs in two places:

1. 'LTRScoringQuery.CreateWeight' or 'LTRScoringQuery.createWeightsParallel'. Here is the loading stage, timeout directly end is acceptable.

2. 'ModelWeight.scorer'. This is a stage that evaluates each Doc and can catch the exception, returns the computed document.

 

Issue Links

• links to: GitHub Pull Request #1690
• links to: GitHub Pull Request #1693