The elusive question " How much swap space do I need to configure? " remains. As always the answer is " It depends. " We have looked at why and how swap space is used and configured. I hope we have shed some light on the elusive dark art of virtual memory. If your system is using swap space, the problem is simple; it has breached, at least the lotsfree threshold and vhand as paged-out part of, at least one process. This is a classic symptom of a memory bottleneck. If the situation persists, you may see a significant increase in system-level processing ( vhand executing) as well as a significant increase in system-level IO ( vhand posting data pages to the swap area). I was once asked how to tune a system for best swap space utilization. My answer was simple: Buy more memory.
