How to use Activity Monitor to make your Mac faster

Activity Monitor for Mac

Activity Monitor is a little know gem of an app hidden in the Utilities folder in your Applications folder. It can look daunting when you first launch it but once you look past the information overload and find out what to focus on it can become an invaluable tool to make your Mac run faster and smoother.

Find yourself staring at a spinning beach-ball cursor regularly? Do you hear your computer fan start up regularly? Are some apps slower than usual? Activity Monitor will tell you why and help you fix some of those problems.

When you first start Activity Monitor it will show you the CPU tab:

The long list of names in Activity Monitor contains all the processes running on your computer. These are not just the Applications you’ve launched but also all the background processes needed to run your computer and Mac OS X.

The processes are ordered by % of CPU usage. This is the first tool in Activity Monitor you can use to spot problems. As you can see in the screenshot here at one point iTunes was using a lot of my computer processing power. That’s something to keep an eye on. In this case I had just started iTunes and it was collecting and reshuffling some data and then once it was done it dropped down to below 5% again. Sometimes however you’ll see that a app you haven’t been using for a while is using a lot of CPU power.

As soon as you see an application persistently using a large percentage of your CPU you should ask yourself if you really need to have it open and then consider closing it.

You might not recognize all the running processes and blindly closing them is never a good idea and can lead to crashes and data loss. What I usually do when I see a process using a lot of CPU is Google its name.

That is how I found out that Spotlight was trying to index my Time Machine disk with a process called “mds” that claimed 80% of my CPU every time Time Machine started backing up. I excluded my Time Machine disk from Spotlight and my MacBook Pro became responsive again during back-ups.

The next thing you can do is order these processes by ‘Memory”. Your computer has a fixed amount of Random Access Memory (RAM) to work with, and some apps use more than others.

If Mac OS X runs out of real memory it uses Virtual memory, or a piece of the slower harddisk instead of your faster RAM chips. It is an elegant but slow solution. If your computer is using a lot of Virtual Memory you might want to consider closing down some apps or even upgrading to more RAM.

Conclusion
Activity Monitor can help you analyze your computer usage and fix problems. Make a habit out of starting it up whenever you see the Spinning Beach-ball or when your computer feels slower than usual.