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From: "vlsi (@vlsi)" <noreply+vlsi@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Tue, 01 Jul 2025 15:50:38 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #3693: Overhead of uncontended use of ResourceLock
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Apparently, the major part of `ResourceLock` overhead comes from 
* `org.postgresql.core.QueryExecutorBase#setTransactionState` (we could make a private variation that does not grab the lock)
* `LruCache.borrow/put` <-- we could replace this with `synchronized` (the cache does not execute IO, so it is loom-safe with all JDKs)
* `org.postgresql.jdbc.PgStatement#executeInternal` <-- this is probably executed under a lock, thus synchronization there might be removed

I wonder if it can make noticeable difference with benchmark like https://github.com/pgjdbc/pgjdbc/blob/5be3c937cc6bdc1c753634881195cf0a0f7bb8c1/benchmarks/src/jmh/java/org/postgresql/benchmark/statement/ProcessResultSet.java


<img width="882" alt="Image" src="https://github.com/user-attachments/assets/33be4915-bf6c-45c2-bb6b-8c956cc46384" />

<img width="882" alt="Image" src="https://github.com/user-attachments/assets/166bac79-301f-41c0-9533-a96fed1966bf" />