Hi,
This is a problem I have almost solved in antiX Openbox alpha1 by configuring zram, but it is only a turn around. Here is a good article on the Archlinux wiki about how to configure swappiness:
The swappiness represent how much the kernel prefers swap to RAM. Setting it to a very low value, meaning the kernel will almost always use RAM, is known to improve responsiveness on many systems. To do that, simply add those lines to /etc/sysctl.conf:
vm.swappiness=20
vm.vfs_cache_pressure=50
To test and more on why this may work, take a look at this article.
