What's up with my Virtual Memory?

Question

I've got a MacBook Pro 15" 2Ghz Core i7 running the 10.8.4 with all updates and 16gb of ram. I notice a couple of odd things over the course of a multiday session:
- Over a few days of usage launching and quiting most apps but with Mail, Terminal, LaunchBar and Safari running constantly, memory and virtual memory usage grow to the point where I have only a few dozen Mb of ram left and over 12 Gb of Virtual Memory consumed.
- Odder still is never, ever, in any session regardless how long, do my virtual memory statistics show more than 14 hits, not 14%, 14 all during boot time, despite hundreds of thousand of page-ins and lookups, and millions (22 million + this session) page faults.
I've noticed that Safari is the main culprit with memory consumption as it only frees up the bulk of any used if quit and relaunched. Even closing all tabs and windows has little to no affect on memory or virtual memory usage, but I have no idea why lookups once the machine is booted never, ever result in a hit despite a constantly growing number and size of swapfiles. Its almost as if Lion is encrypting the swaps but then doesn't have access to read them though I don't know how that might come about.
Anyone care to offer suggestions as to cause or debugging/troubleshooting tips?
Other notes:
This has been happening at least since 10.7.x.
Aside from apps listed above, other frequent apps are, Adobe Photoshop 5.5.x, Lightroom 5, LaunchBar, and ocassional MS Office 2011 with all updates.
Thanks,
David

Answer 1

About OS X Memory Management and Usage
Using Activity Monitor to read System Memory & determine how much RAM is used
Memory Management in Mac OS X
Performance Guidelines- Memory Management in Mac OS X
A detailed look at memory usage in OS X
Memory Usage Performance Guidelines- About the Virtual Memory System
Understanding top output in the Terminal
The amount of available RAM for applications is the sum of Free RAM and Inactive RAM. This will change as applications are opened and closed or change from active to inactive status. The Swap figure represents an estimate of the total amount of swap space required for VM if used, but does not necessarily indicate the actual size of the existing swap file. If you are really in need of more RAM that would be indicated by how frequently the system uses VM. If you open the Terminal and run the top command at the prompt you will find information reported on Pageins () and Pageouts (). Pageouts () is the important figure. If the value in the parentheses is 0 (zero) then OS X is not making instantaneous use of VM which means you have adequate physical RAM for the system with the applications you have loaded. If the figure in parentheses is running positive and your hard drive is constantly being used (thrashing) then you need more physical RAM.
Adding RAM only makes it possible to run more programs concurrently.  It doesn't speed up the computer nor make games run faster.  What it can do is prevent the system from having to use disk-based VM when it runs out of RAM because you are trying to run too many applications concurrently or using applications that are extremely RAM dependent.  It will improve the performance of applications that run mostly in RAM or when loading programs.