linux.dsplabs.com.au/forums

[QuantumKnot]

Here is a kernel tweak (that doesn't require a kernel recompile for those like Kamil who seemed distressed about it ) that reduces the chance of applications getting swapped into VM when it is clear that there is plenty of memory free (but sucked up by cache). So the kernel has a higher tendency to reclaim memory from the cache rather than swap out our process pages.

http://fedoraguide.info/index.php/Fedora8#Swappiness

Here's an explanation about what this parameter does exactly

http://lwn.net/Articles/83588/
http://kerneltrap.org/node/1044