Macs are wonderful machines, but like any hardware, they can eventually suffer from decreased performance as they get older. Follow these tips for a performance boost!
Use the free SMARTReporter Menu Tool
The SMARTReporter toolbar is a free add-on that checks the S.M.A.R.T. output of your Mac's hard drive, and notifies you if there are any failures or other problems. Bear in mind that this does not work with external drives, only internal drives such as SATA/eSATA/IDE.
Be aware of memory leakage
When you run programs, they use memory (RAM, not hard drive space). The more programs you have running at once, the more memory is needed, and the more performance might suffer. Some programs use more memory than others.
Sometimes when you close programs (or tabs in your internet browser), the programs still hold on to the memory they were using, even though they do not need it any more. Even though this memory is no longer needed, it cannot be used by other programs. This is known as memory leakage, and it slows down performance.
You can check what processes are running by opening the Activity monitor (press "option - command - escape"). You can end processes in here - but only end processes if you know what they are, and that ending them is not going to cause the system to fail!
Do a Clear-out of your Login Items
Startup can become quite slow, and often it is programs or updaters running themselves every time your Mac starts up. Many of these are not things that you actually use.
You can check what is running on startup by opening system preferences, looking in the accounts pane, and then checking the login items.
Disable un-used features
Features like Universal Access and Bluetooth use power and memory, but you probably don't use them. They could be slowing down your system. Open the Apple Menu, go to System Preferences, and check which features are enabled. Disable anything you don't need.
Ensure a cool environment
It is important for Macs, as with any computer hardware, that they are kept cool. You should store and use your computer in a cool, dry environment. The optimal temperature for Macs to maintain best performance is between 15 and 22 degrees celsius.
You can help to ensure this by downloading and running fan Control - a utility which automatically adjusts your fan speed according to the temperature of your system.
Disable un-necessary widgets
Macs automatically run many widgets that do things like report the weather, or show you the cinema times for the latest films. It is likely that you don't use these, but they do use a small amount of memory. It is worth disabling these if you don't refer to them.
Don't let your disc space run too low
Mac OS X uses a lot of Virtual Memory (VM, or RAM). It also requires free disk space on your main hard disk in order to run properly. If your startup disk is nearly full, you will notice a drop in your Mac's performance.
Carry out a Permissions Repair
This is a frequently recommended trouble shooting step for Macs. To perform a permissions repair, launch Disk Utility, select the boot drive, and click "Repair Disk Permissions".
Repairing the disk permissions checks certain files and folders on your Mac's hard drive and examines them against what Mac OS recommends them to be. If there are differences, Mac OS will revert to the recommended settings.
Incorrect permissions on files can cause you to run into problems when trying to carry out actions such as running new programs, printing, or even booting up your Mac.
Performing a permissions repair is more of a trouble-shooting step than a regular maintenance activity.