By repairing disk permissions, running maintenance scripts, and buying more RAM, you can dramatically increase the performance of your Mac, whether it’s an old iBook or a snazzy new Macbook Pro.

Disk permission trouble

Does your Mac take a lot longer to boot than it did when you were first lifting it out of the designer packaging? One very common reason why is that problems have cropped up in the disk permissions.

People rarely fix this, because it is a little bit tricky. That said, it’s not something you cannot do in ten minutes with these instructions. First off, you cannot repair the disk that you are running Mac OS off of (though if you just want to repair permissions, that is possible). What you need to do is get either: (a) any Mac OS X installation disc or (b) system recovery discs that accompanied your computer.

Next, you need to reboot, using the disc instead of your hard drive. For most Macs, you do this by putting the disc in, rebooting, and then tapping or holding either ‘c’ or ‘option-c’ during the period before the login window appears. For instructions specific to your machine, check the manual.

Once the computer has booted from the disc, you will see the Mac OS X installer. Obviously, you don’t want to install OS X over top of a perfectly good copy. Instead, just select a language for the menus (English, since you are reading this) and then select the utilities menu from the top of the screen. From the list, choose Disk Utility. This is the same program as the one that lives in your Applications/Utilities folder, by default.

Once inside, just select your hard drive and click “Repair Disk Permissions.” Let that run, then click “Repair Disk.” Any problems that have cropped up with the structure of your filesystem will be repaired. Once done, quit the program and restart your computer, making sure not to hit the keys that will make it boot from the disc again.

Maintenance scripts

Mac OS X is built on Unix: an operating system originally designed for big, powerful computers that run all the time. Especially for those of you using laptops, this causes a small problem. There are three maintenance scripts - daily, weekly, and monthly - that run automatically late at night, provided your computer is turned on at the right time. If it is asleep or off, they will never run. To check when the scripts last ran, you can open a Terminal window and use the following command:

ls -al /var/log/*.out
It will output the last usage time for the daily, monthly, and weekly scripts.

There are two ways you can get around this. The first option is to run the scripts manually. To do so, open a Terminal window and type:

sudo periodic daily weekly monthly
The sudo command (short for superuser do, and pronounced soo-doo) tells the system to run the command as if you are a superuser. As such, it will ask you for an administrator password, which is simply the user password for any logged in user with an administrator account.

The easier way: get the free MacJanitor utility and run it every once in a while. Because running the scripts requires administrator access, the MacJanitor program will still ask for that password.

RAM hunger

While upgrading your RAM isn’t free, it is definitely the most cost effective thing you can do to bolster the performance of your Mac. If you’re like me, you are generally running an email program, a web browser, a text editor, and instant message client, and a music player at any particular time. Once your computer reaches the limit of how much it can handle with physical RAM, it starts using your hard drive like RAM (virtual memory). This is bad for two reasons: (a) your hard drive is much, much slower than RAM at dealing with data and (b) the RAM-like hard drive activity gets in the way of other programs using the drive efficiently.

I would say that running a recent Mac with less than one gigabyte of RAM is probably unwise. I doubt the price of the RAM is less than the ongoing price of frustration. That said, if you never run RAM-hogging programs like Photoshop or Firefox, you may be just fine with what you have. The Activity Monitor program in Applications/Utilities can give you a sense of how much RAM, if any, you have free at any particular time. This can also be done using the ‘top’ command in the Terminal.

It should be noted that people with Macbooks have an even greater need for extra RAM, since those machines do not have independent video RAM and therefore use the same chips for more tasks.

This node was originally a post on my blog, at: