We are running 10 web sites on windows 2000 server, JRun2.3, Microsoft IIS 5, Oracle9i, 1 gig RAM and RAID level 5. This combination utilizing 40% of RAM out of which 20%(max) and 6-7% (avg) is of JRun2.3. We migrate to JRun4 and tested each site individually. When all the sites are running together the maximum memory utilization reaches upto 70% with some spikes to 95% consumption out of which JRun4 is consuming 50%(max) and 15-20% (avg). Can we optimize the memory utilization of JRun4.