See
https://docs.oracle.com/en/java/javase/24/gctuning/garbage-first-g1-garbage-collector1.html#GUID-98E80C82-24D8-41D4-BC39-B2583F04F1FF
there is the same issue in the gctuning doc for jdk21 .
The mentioned G1EnableStringDeduplication is long gone, seems it is now UseStringDeduplication (since jdk11 or even loger).
https://docs.oracle.com/en/java/javase/24/gctuning/garbage-first-g1-garbage-collector1.html#GUID-98E80C82-24D8-41D4-BC39-B2583F04F1FF
there is the same issue in the gctuning doc for jdk21 .
The mentioned G1EnableStringDeduplication is long gone, seems it is now UseStringDeduplication (since jdk11 or even loger).