Socket Descriptors getting fully utilized

[neha]

This topic is discussed many times but nowhere i found my answer. Is there anyway we can explicitly release the used file/socket descriptor using java code or through RMQ console without restarting it.

[neha]

Also, if we are increasing the socket descriptor limit, it has to be below what limit is set at OS level?
e.g. If at OS level, file descriptor limit is set to 4096, then for RMQ also, file descriptor limit has to be <=4096 ?