The memory usage of the Class Metadata (1GB) and Internal (2GB) sections seems to exceed expectations by a significant amount.

• Internal(2GB)
  In NMT, the Internal memory is allocated using ByteBuffer.allocateDirect, which represents off-heap memory. The excessive memory overhead in this section may be due to the introduction of Netty in the project.

• Metadata(1GB）
  The high memory consumption of the Class Metadata could be a result of the JVM's default setting, UseCompressedClassPointers.
  For more information, you can refer to this link: https://mp.weixin.qq.com/s?__biz=MzkyNTMwMjI2Mw==&mid=2247489471&idx=1&sn=11fb0d30c8bcea50b1bda0b1cd2a6595&chksm=c1c9fb27f6be72314b28d163146ecaa11b298ac9856625cfdc8909d464be6d8b220ef615fd69&scene=178&cur_album_id=2192236085064302593#rd

@zhoujinsong
Should we introduce these two parameters in the JVM arguments of AMS to control off-heap memory size?

-XX:MaxDirectMemorySize

-XX:MaxMetaspaceSize