I have 16GB of RAM installed on my Mac Pro (2008) on OS X 10.6.7. I notice that a small page out is occuring and 1 MB of Swap has been used, per the Activity Monitor. What I don't understand is why; I have over 13 GB of free RAM available. I've attached a screenshot of my Activity Monitor.
Thoughts?
Thanks.
Mac Pro 8-Core 2.8Ghz, Mac OS X (10.6), 16 GB RAM
Normal. There's always at least one swapfile.
Although some of those counters and the pie chart are instantaneous indicators, the PageOuts and Swap Used are not even high-water marks, they are more like water meters -- they are telling you the total amount you have moved since Startup. So that says that in the entire time your Mac has been on since last restart, that is the total amount of pageouts and swap used.
Thanks for the support reference. I've read that before. I guess I don't understand "why" I would have page outs. But it sounds like a swap file eventually gets created.
About OS X Memory Management and Usage
Reading system memory usage in Activity Monitor
Performance Guidelines- Memory Management in Mac OS X
A detailed look at memory usage in OS X
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.
"But it sounds like a swap file eventually gets created."
Not eventually, always (in /var/vm).
As was stated, sometime since you booted you used something (or somethings) which required swap.
Swap Used Even With Plenty of Available RAM
