[LUCENE-8884] Add Directory wrapper to track per-query IO counters

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: core/store
• Lucene Fields: New
• Assignee: Michael McCandless
• Reporter: Michael McCandless
• Created: 26/Jun/19 12:33
• Updated: 28/Aug/22 15:47

Description

Lucene's IO abstractions (Directory, IndexInput/Output) make it really easy to track counters of how many IOPs and net bytes are read for each query, which is a useful metric to track/aggregate/alarm on in production or dev benchmarks.

At my day job we use these wrappers in our nightly benchmarks to catch any accidental performance regressions.