OutofMemory Error while loading MIB files using loadMib method of adventnet java API

Hi,

      I am getting java OutOfMemoryError problem in my current web application .. following thing explains the problem in detail

a) java heap space given in application is :334MB PermGen space: 64MB
b) every time fetching & setting data to and from device MIB file will be loaded.
c) Once the operation done.. snmptarget will be released

      I am getting OutOfMemoryError while loading LACP, LLDP, RSTP mib files... initially this problem will not occurs after doing some operation i am getting this error.

        I don't want to increase the Heap size unless i don't have the other solution ... this application is developed quite long back... everywhere in code they are loading MIB and then release..

Please give me solution if any one knows ... how much memory it will take to load those kind of standard MIBS????? is there any other way to find solution for this???