At admin console i show that java memory continuously shrinking down and shrinking up . and it has been used upto 99% in my case. is there need to increase the heap memory.
Shrinking and growing is the normal behavior of Java Virtual Machine (JVM). It removes “garbage” from time to time. You don’t need to increase memory if you are not running into problems with the server (people can’t connect, server freezing, etc.).
Thank you @wroot for your answer . I’d like to give some information about my openfire setup. I have a 8gb Linux server and about 70000+ registered user on openfire(which running on a default heap settings) and average rate of active user 500 -700 at a time , so how many active user handled by openfire at time. and when a need to increase the heap.
This is impossible to say how many it can handle. It depends on how this users are using it (how many contacts, messages, how big messages, etc.). So you can only watch the server and see if it behaves correctly. If JVM memory gauge is always somewhere near the 100% usage, you can increase it just in case.