On Thu, Feb 3, 2011 at 7:18 AM, mcclnx mcc <mcclnx at yahoo.com.tw> wrote: > kernel is: > > 2.6.18-194.26.1.el5 #1 SMP Tue Nov 9 12:54:20 EST 2010 x86_64 x86_64 x86_64 GNU/Linux > What sort of application? Is it 64-bit aware? What is the monitor checking? Also, there are some things to keep in mind if it's a Java-based application. You have to set heapsize differently (or at least, used to have to) on 32-bit vs 64-bit Java.