Increasing Virtual Memory on a Mac

By Jefe Nubarron

Increasing Virtual Memory on a Mac
i Justin Sullivan/Getty Images News/Getty Images

You will likely be unaware of your Mac's virtual memory (VM) until you find that its performance has slowed to a crawl. This is a temporary memory reserve, from which a Mac's Random Access Memory (RAM) borrows to perform operations. RAM is fast physical memory. VM is much slower swappable memory, located on a disk drive. When needed, a Mac will dynamically allocate additional virtual memory, and you can do little to tune VM allocation. However, keep in mind that a Mac uses free disk space as virtual memory, so a full boot disk can cause problems.

Reset your Mac's parameter random access memory (PRAM) and nonvolatile random access memory (NVRAM). Press and hold the "Command," "Option" and letters "P" and "R" on your Mac keyboard as you start the computer. Listen for the second set of chimes and release.

Free additional disk space on your boot volume. VM on a Mac requires free disk space on your startup disk. If your startup disk is nearly full, your Mac's performance will be degraded. Delete files you no longer need. Movies take up a lot of drive space, which makes them good candidates to delete.

Consider installing a larger hard drive in your Mac. If you cannot find enough files to delete on your boot drive, it may be time for a larger drive. It is best to consult with an expert or Apple Genius for this delicate process.