Fedora Constantine, SYSRQ and needless swapping

By default, fedora disables the SYSRQ functionality of the kernel, for some reason. To enable it, either add sysrq_always_enabled at the end of your kernel line in /boot/grub/menu.conf, or edit /etc/sysctl.conf, changing

kernel.sysrq = 0


kernel.sysrq = 1

Some kernel updates on fedora also have the tendency to write to swap needlessly, even though you have loads of RAM available, to stop this, edit /etc/sysctl.conf again, and add the following two lines

# Controls the swapiness of the machine
vm/swappiness = 0

To just temporarily disable it, do

echo -n 0 > /proc/sys/vm/swappiness

as root

***These tips are applicable to almost any GNU/Linux distribution, not necessarily for Fedora alone