Increase Java 21 virtual thread performance via get rid of synchronized

[asmburning]

What the problem is : Java 21 virtual thread might hinder its scalability when using synchronized

Based on Java doc Java 21 virtual thread
A virtual thread cannot be unmounted during blocking operations when it is pinned to its carrier. A virtual thread is pinned in the following situations:

1. The virtual thread runs code inside a synchronized block or method
2. The virtual thread runs a native method or a foreign function (see [Foreign Function and Memory API]

Pinning does not make an application incorrect, but it might hinder its scalability.
Try avoiding frequent and long-lived pinning by revising synchronized blocks or methods that run frequently and guarding potentially long I/O operations with java.util.concurrent.locks.ReentrantLock.

Describe the solution you'd like

Use java.util.concurrent.locks.ReentrantLock instead of synchronized