Swapping from memory to disk can be extremely expensive.
Avoid a high Linux swapping rate on the system, because this impacts
the database performance. When you size your Linux system, bear in
mind that there is no large amount of free memory for the Linux buffer
cache. Especially when running as a guest under z/VM, do not define
the virtual machine larger than you really need. Consider decreasing
the size of the virtual machine and watch the Linux swapping. If you
decrease the virtual machine and no swapping occurs, then the smaller
machine size may be acceptable.
