A customer strolled into our South Burlington store the other day with a 17-inch unibody MacBook Pro, fully decked out with 8GB of RAM. Somehow, after a few hours of layout work in Quark XPress, the machine would begin to bog down and “beachball” as if it were a Bondi blue iMac G3 with dial-up Internet access.
He’d just spent the day working on a high-resolution project. By 4:00, he said, the system was so slow that he had to restart, and that restarting fixed things every time. I theorized that logging out and then logging back in would do the same thing. But rebooting is very frustrating and doesn’t address the root cause of the problem.
The customer came in with the laptop sleeping and the problem in full force. I fired up Activity Monitor and immediately saw that there was no memory available. Mac OS X was deep into virtual memory reserves, which was undoubtedly causing the memory issues.
I’ve seen programs with memory leaks before—it’s actually rather common. Usually, though, it’s apparent from Activity Monitor which application is to blame. Unfortunately, this was not the case here.
Taking a step back, I remembered that the 15- and 17-inch laptops now have discrete graphics cards as well as integrated graphics cards. The more powerful discrete cards do not share RAM with the main system and should free up memory as compared to the integrated option. I checked the Energy Saver preference pane to view the graphics performance settings. Sure enough, the machine was set to “better battery life” instead of “better performance.”
Selecting the higher performance option enabled the discrete graphics processor, stopping the computer’s use of main RAM as video RAM. It also had the wonderful effect of speeding up graphics-intensive operations such as Quark.