[OAK-6683] Use less resource intensive method to determine number of docs in lucene index

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.7.8, 1.8.0
• Component/s: lucene
• Assignee: Chetan Mehrotra
• Reporter: Chetan Mehrotra
• Created: 20/Sep/17 10:44
• Updated: 29/Sep/17 10:09
• Resolved: 20/Sep/17 11:55

Description

Currently LuceneIndexInfoProvider opens a DirectoryReader via OakDirectory which leads to very high memory consumption due to current design of OakDirectory (see OAK-3132).

As we just need to determine the numDocs we can directly use the SegmentInfos to determine this information in a more efficient manner and avoid creating whole DirectoryReader