Yeah I've heard of the Java 1-2 greenthreads, but supposedly those were M:1, ie you could only run them on one core. At least this SCO release note linked from Wikipedia says that: https://www.sco.com/developers/java/j2sdk122-001/ReleaseNote... And the pros are more about compatibility than performance
How have you found a SCO note, which never did nothing relevant for Java?
Here from Oracle, as historically taken from Sun documentation for JDK 1.1.
=> Many-to-Many Model (Java on Solaris--Native Threads)
https://docs.oracle.com/cd/E19455-01/806-3461/6jck06gqk/inde...