Hi all: The /sys/devices/system/memory/probe file does not show up, here is what I did: patched 2.6.17-rc5 with: 2.6.17-rc5-mm1 patch-2.6.17-rc5-mm1-lxc2 ran make menuconfig on the old config file setting: Memory model to Sparse Memory Allow for memory hot-add to y Memory Hotplug to y compiled and booted the kernel with mem=512M The .config file is here: http://developer.osdl.org/jnorman/config_ia64 Thanks. Jake Norman