OS X Mountain Lion Server For Dummies

Putting Enough RAM in Your Server

RAM is important for speed in the OS X operating system, and this is particularly true for servers. Server applications can often run faster when you add RAM. More RAM also increases the number of simultaneous client connections that the server can handle without bogging down. On the other hand, filling a Mac Pro with the maximum 64GB of RAM will cost thousands of dollars (if you buy it from Apple), which is a big waste if the server isn’t using it.

The minimum amount of RAM you should consider is 4GB. This amount should provide acceptable results for up to 200 users for light, occasional uses, or for a small network of fewer than 10 computers for file sharing. But keep in mind that the Server configuration of the Mac Pro starts at 8GB of RAM.

If you’re not sure if your system has enough memory, you can check usage after you’ve been running the server in normal use for a few hours. You can use Activity Monitor (in the server’s Utility folder) to keep an eye on RAM usage. At the bottom of the Activity Monitor window, click the System Memory tab (see Figure 2-2). Look at the Page Ins and Page Outs numbers. If the size of the page outs is more than 5 to 10 percent of the page ins, the operating system has to write information from RAM to disk because it doesn’t have enough RAM, which translates to slower server performance. If that happens, adding ...