Avoid synchronized block or methods

[reda-alaoui]

According to https://docs.oracle.com/en/java/javase/21/core/virtual-threads.html#GUID-04C03FFC-066D-4857-85B9-E5A27A875AF9:

A current limitation of the implementation of virtual threads is that performing a blocking operation while inside a synchronized block or method causes the JDK's virtual thread scheduler to block a precious OS thread, whereas it wouldn't if the blocking operation were done outside of a synchronized block or method. We call that situation "pinning".

IMHO, all synchronizd blocks or methods should be replaced with ReentrantLock usage.

[He-Pin]

Not all, only io bound I think.