[CentOS] Flushing RAM contents?

Mon Feb 11 20:05:10 UTC 2008
Scott Ehrlich <scott at MIT.EDU>

A user wants to time a command/program/application and ensure the full 
contents of that command's data management has been flushed from RAM/cache 
and saved to disk.  Is there a way to ensure the cache/RAM is flushed to 
disk, or is the flushing a function of the kernel or the application?

This happens to be on a 64-bit Intel system with 64-bit CentOS 5, fully 
patched.   But even if the system were an out-of-box 64-bit install, 
unpatched, would it make a difference?

Thanks.

Scott