[shawnz]

Swap is not meant to enable you to escape the memory demands of your workload. If your workload requires more physical memory than you have, then swap will probably not help you.

However just because your software allocates data in memory doesn't mean it needs to be there. Rarely used memory could be swapped out to cache more frequently used files on disk instead, increasing the overall throughput of the system. This could be true whether or not you have an excess of physical memory for your workload.