[LUCENE-7778] Remove synchronized from high-contention methods on RAMFile

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: core/store
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Steve Mason
• Created: 11/Apr/17 16:02
• Updated: 28/Aug/22 15:13

Description

When benchmarking RAMDirectory access via multiple threads the methods RAMFile::numBuffers and RAMFile::getBuffer show up blocking threads fairly frequently

By removing the synchronized keyword from these methods our internal benchmarks show a 2x performance increase under concurrent load.

I don't think removing synchronized from these methods is a problem as they are read-only and write access to these fields is not synchronized. LUCENE-2779 also implies that some ofthe locking on RAMDirectory is not necessary

Issue Links

• links to: GitHub Pull Request #183