I post this hoping to help those users who, like me, are experiencing high CPU usage and massive memory leaking with OS X core services and apps, leading to slow performance and battery drain.
I’ve tried everything mentioned, but found the right combination of steps to follow. I’ve tried this with seven different Apple computers, including mine, and has worked well so far. I applied this method yesterday to give these process a 24 hour window to fail again, so far everything good.
First step: disconnect any external or secondary monitors, if any is present. The video memory allocation leak can also happen if you have a system with an integrated card, like Intel, with no external monitors attached.
Second step: Shut down your machine and enter Safe Mode (press shift once you turn on your computer again, more info below). Once you’re there, fix your disk permissions.
Guide of how to access Safe Mode: OS X: What is Safe Boot, Safe Mode?
Third step: From Safe Mode turn off your machine again and reset your System Management Controller (SMC). There are different methods, depending on machine, to do this. To know what method applies to yours read the following guide.
Fourth step: Once your machine completes a full boot after resetting the SMC turn it off again and reset your PRAM (THIS IS THE MOST IMPORTANT STEP, BUT THE PREVIOUS ONES ARE ESSENTIAL FOR THIS ONE TO WORK). The PRAM stores small bits of data that indicate our Apple computer how to interact with the devices connected to it, including monitors and video cards. It also affects software.
To reset it you should hold the OPTION, COMMAND, P and R keys in your keyboard immediately after turning on your machine again.You’ll hear the start up chime, continue pressing the keys until the machine boots and the chime starts A SECOND TIME, then release. IF YOUR YOSEMITE INSTALLATION LOCKS UP AT A BLACK SCREEN AFTER THIS, DONT PANIC! It’s normal, just turn off your computer and let it boot again.
More info about PRAM: OS X Mavericks: Reset your computer’s PRAM
Voila, reconnect your external displays and enjoy your system.