We just moved from a 32-bit machine to a 64-bit machine. We have quickly ran out of memory despite the new boxes have twice as much ram as the old boxes. Running a simple ps command will illustrate the problem. New machine: 132 prod-Charlotte1-node1 ~/public_html/rearch/cgi-bin ps aux | grep ps root 293 0.0 0.0 0 0 ? S< May09 0:00 [kpsmoused] xamine 2267 1.0 0.0 63728 928 pts/3 R+ 16:50 0:00 ps aux xamine 2268 0.0 0.0 61172 752 pts/3 S+ 16:50 0:00 grep ps Old machine: 132 prod-116431-node1:/home/xamine ps aux | grep ps xamine 23191 0.0 0.0 2332 768 pts/6 R+ 15:41 0:00 ps aux xamine 23192 0.0 0.0 3668 692 pts/6 S+ 15:41 0:00 grep ps Notice that the ps process is using 63M of VIRT mem vs 2 on the old machine. New Machine: Enterprise Linux Enterprise Linux Server release 5.4 (Carthage) Red Hat Enterprise Linux Server release 5.4 (Tikanga) Old Machine: Red Hat Enterprise Linux ES release 4 (Nahant Update 4) Thanks for any thoughts you have!