Are you saying that this box is at 95%
after adding swap?
1. You cannot use more than 100% of your virtual memory. If you try, some horrible error will occur. At the time this swapinfo was performed, the box was nearly out of virtual memory. Maybe that 1/2 GB left is enough, but if not, the box will be unable to create new processes.
2. Originally Unix required swap area for any virtual object. So you first 6 GB of swap would simply enable the use of your 6GB of physical memory. Any swap after that gives you additional space over the 6GB. Under this scheme, you could in theory swap everything out. You have the kernel parameter swapmem turned on (which is wise). So the kernel pretends that you have an extra swap area which is sized at 4.7 GB. This means that you no longer have enough real swap to completely empty memory. The kernel computes the size of this imaginary swap area as a fixed percentage of the physical memory size.
This box fully consumed physical memory some time ago. This does not affect stability but it can affect performance. To see how bad that is, you want to watch this box's scan rate. (sr in the vmstat display).