How to know which process is causing high memory usage on DB?

I've got one Onesight alert mail stating below: Short Description: Onesight Alert: ZEUS DB Monitor (zeus04) Description: Solaris 5.8: vmstat memory(free) - Free Memory for zeus04 2065112 8:06:02 AM IST 2 min Free Memory below 4GB: Value was 3,965,488 , threshold is 4194304.0 - 12:36:02 AM IST Upon issuing OS level commands below I got the following understanding: prstat This command returned me the top process ID(3578) which is using more CPU. then, prstat -Lm -p 3578 this command returned me the following output: PID USERNAME USR SYS TRP TFL DFL LCK SLP LAT VCX ICX SCL SIG PROCESS/LWPID 3578 oracle 0.7 2.3 1.6 0.0 0.0 90 4.4 1.5 483 235 1K 0 java/838694 3578 oracle 0.3 0.0 0.2 0.0 0.0 95 1.5 0.1 52 8 41 0 java/839336 I thought some Java process would be running so asked the Apps Support team and the said: we believe this process is related to the Oracle OEM agent Java process Now how do i drill down the issue and resolve because free memory is going below 2GB almost everyday. DB environment details: OS:Solaris 5.8(Unix) DB version: 10.2.0.5 Memory size:64 GB Regards, Ritu