Short answer: You don’t.

More interesting answer: You only think you want to do that, what are you, some kind of a Microsoft Windows user or something?

Actual answer: You probably don’t, but if you do, it is a rather fun and interesting thing to try. But really, mostly, don’t.

I recently discovered a nifty utility that is automatically installed in OS X. It is called “Activity Monitor.” Essentially this is a graphical version of “top” melded with a system monitoring utility. “top” is a command line cui-graphic based utility which is a souped up version of the command line utility “ps”.

“ps” and similar unix-like commands (and the Mac OS X runs on a Unix-like base) allows you to look at the files that your system has created to represent processes. Processes are roughly the same thing as programs, so if you open a terminal and you type

ps -A | grep bash

then you’ll get something like

21835 ttys000 0:00.06 -bash
22698 ttys000 0:00.00 grep bash

Which shows you that you are running bash (that is actually what your terminal is using) and that you are running an instance of grep that is looking for the word “bash” … which is funny, of course.

These things that look like files are only files because everything in unix is a file (even your keyboard and your monitor) but in this case a special set of files that represent processes.

“top” is a way of organizing what ps give you in a table form, and might look like this:

Activity Monitor is TOP but not in a terminal and with additional functionality. It looks like this:

The top part is just “top” but mouse-able, and the bottom part is a set of the usual system monitoring utilities.

I guess I was playing around with this stuff when it occurred to me that if I knew something, then I should fiddle with it. Otherwise, well, why even exist? So I started wondering what processes were running that should be turned off to save memory and processing cycles. Frankly, I did not expect that there would be many on a general use desktop. I don’t turn anything off on my Linux desktop. But, on laptops or on specialized desktops one might want to do this. Unless you designed the implementation of the system you are using, there is a pretty good chance that there is something running that you don’t need. On my laptop, for example, I turn off the bluetooth managing process because the machine does not have a functioning bluetooth thingie, so why bother with that?

I have a couple of Linux machines and I can fiddle with the all I want, and frankly I’m not that interested in fiddling much under the hood with a fairly new and capable and properly functioning iMac. But I did want to see what was there. So I googled it.

The answer that came up made me laugh, because they are so axiomatic of the Culture of Mac. Here’s a few examples:

A person asks on a forum:

OK, I am a windows dude… I need to turn off unnecessary processes on a Mac. … What do I do on a Mac? I need it to be permanent, not temporary (like I know how to shut off iTunes helper for a session- I want it off after restarts, too. .. Also, I want to pare this mac down to just the essentials- any advice for what to kill, and what I should not touch? … Thanks!

And among the answer we find:

Tallest says “You should let OS X do its thing. You don’t need to turn of those processes. OS X knows how to manage RAM and processing power.”

The person originally asking responds:

No— you do not understand. … I NEED to turn off iTunes Helper. I NEED to turn off Indexing. I NEED to turn off Software Updates, etc. etc.

A Mac experts chimes in with some advice of what can be removed easily and how to do it (I’ll get to that here later) but adds:

Mac OS X really does manage memory and processes much better than Windows does. Aside from those items, I’d leave everything else stock. Without going deep, there isn’t much to change.

Then the guy called “Tallest” chimes in:

I’m not trying to be condescending; I’m genuinely curious. Why do you need every last thousandth of a gigahertz and bit of RAM (yes, bit) on your machine?

And someone else throws in the helpful comment:

You could just install the Darwin subsystem on your Mac.

And someone else:

@Tallest : Just stick to the Question someone asked. if you can not answer straight, shut the **** up

and then someone else notes:

Tallest won’t be able to respond. The “banned” under his name indicates that he’s been, well, banned

So, that’s a pretty good example of what happens when someone who is not a dyed in the wool Mac user asks a question on a Mac forum. There was a good answer given (which we’ll get to shortly) but first the person had to learn that they should not be asking such questions!

There are two things you need to know about this, maybe three:

1) Most Unix bases systems are designed pretty well and the processes you’ve got going are optimized and you should mostly not worry about them.

2) Most of the processes that you don’t actually use and could thus turn off are not using much in the way of resources so turning them off does not do much.

3) You can’t easily look at the name of a process and tell if it is important unless you really know what you are doing. For instance, you might see processes that seem to be related to “paging” and you might think you don’t do that, but “paging” is basic memory management and taking that out of your system would be the equivalent in your head of taking out your hippocampus.

Having said all that, there is this really cool thing you can do.

First, go to the command line in a terminal. Then type in this:

ps -A > process.txt

ps with the paramater “-A” prints out a set of processes running on your computer that would include those you might want to consider disabling. The greater than sign sends the output of ps -A somewhere. The “process.txt” is the name of a file you just made up, and since it is to the right of the greater than sign, that is where the output of ps -A will go. So you just made a file with a list of candidate processes to eliminate.

Then go to this web site:

Know your Mac OS X processes

and upload your process.txt file (it will probably be in your “home” directory).

Then, you can look at a list of processes linked to version of each processes man file with a short description. If you click on “read more” you see the man file.

In case you are wondering what a “man” file is, I’ll tell you. In Unix World nothing is allowed to be longer than three letters long except the words “Unix”, “Linux” and “Emacs.” “Man” stands for “Manual.” Go to your terminal again and type in

man ps

You now see the “man” file for “ps” … use the space bar to “scroll” down, and type “q” to quit. The web site linked to above basically gives you the man files for the different processes.

Now you can go through all the esoteria such as “syslogd” and “kextd” and “ubd” and find out what all those things are.

So, what are you going to turn off and how?

For the most part there is a maximum of two processes you might want to turn off because they are mostly unnecessary to operating most things on your computer.

1) iTunes Helper. This process sits there and waits for you to plug in an iPod, then it runs iTunes. It may do a few other things, but nothing you need. You can start iTunes whenever you want and if there is an Pod plugged in it will find it. Turning off iTunes helper will probably save you almost nothing. There have been times in the past, though, where iTunes helper did bad things just sitting there, on some people’s machines, so a lot of people turned it off. You can remove iTunes Helper from Login Items under the Accounts preference pane in the System Preferences thingie. It will be replaced later when you restart your computer, which is annoying.

2) Spotlight. Spotlight may be one of the most brilliant, useful things ever invented on your computer. After all, your computer is all about having things, organizing thing, and finding things, and spotlight might be the best utility to do that ever invented. Also, it can be configured for specialized uses other than just being a super search tool. On the other hand, it could also be something you never, ever, use, and thus a true waste of resources, because in order for Spotlight to work it has to index the bejesus out of your hard drive. To prevent Spotlight from indexing your hard rive, add your hard drive to the Privacy tab of the Spotlight preference pane. That is also in the System Preferences thingie.


  1. #1 Joe the Stack
    United States
    January 14, 2013

    If there are a lot of files on your disks, Spotlight can pretty much consume most of your spare CPU cycles, but it isn’t at all clear that it gets in the way of your more important processes, when you are actually exercising them.

    But what about Mail? What about people with 10,000 to 100,000 messages, sometimes all in one mailbox? Spotlight wastes its life indexing them too, if you don’t tell it not to. If you have 100,000 messages, how do you back them up so that you could switch to a different Mac without losing access or continuity? I of course am opposed to the premise itself, but one must be practical when dealing with others.

  2. #2 Eric Lund
    January 14, 2013

    But what about Mail? What about people with 10,000 to 100,000 messages, sometimes all in one mailbox? Spotlight wastes its life indexing them too, if you don’t tell it not to. If you have 100,000 messages, how do you back them up so that you could switch to a different Mac without losing access or continuity?

    Your mailboxes are under a certain directory (~/Library/Mail/Mailboxes on my Mac; presumably the same on your machine unless you have changed a default), so if you can exclude certain directories from Spotlight (as the original post implies), you can hide that directory from Spotlight.

    As for the second question, it depends on whether you need to enable account access to more than one machine, or you are migrating to a new machine. In the former case, you can tell the server not to delete the message for some period of time (I use 30 days, because I read my mail both at the office and on my home machine, and I sometimes use my iPhone for reading mail when I am on the road) after reading it–if you have retrieved the message before on one machine it won’t retrieve it again on that machine, but your other machine can still get it. For the latter scenario, there are lots of backup utilities available, including Time Machine, which is included with MacOS 10.5 and later.

  3. #3 Jonathan Thornburg
    January 15, 2013

    I often run large number-crunching simulations in the background on iMacs (which noone is using at the time) located in one of our teaching labs. I’d love to be able to disable unnecessary background processes which are eating CPU cycles…

  4. #4 Greg Laden
    January 15, 2013

    You can use top or the application I mention to turn off active processes that you “own.” (or become a superuser). Using the guide or man pages, you can decide which would be most risky to turn off.

  5. #5 Emma Lopaz
    January 19, 2013

    How do you turn off unneeded processes on an iMac? is very interesting article about Apple href=””>iMac

  6. #6 Paul
    January 27, 2015

    Who ever wrote this is a complete retard. There are things you can stop or turn off and a lot of the bells and whistle bull crap that OSx comes with is really unnecessary and can be turned off with some easy terminal commands. And fun fact Macs are not as efficient with RAM as they say they are its all bogus. Unless you quit all the process some programs will continue to run underneath the hood because the os puts them in a sleep state but they still take up space regardless. I honestly just dual boot and use Windows 7 like 90% of the time because I get WAY more performance out of my mac then with the stupid apple os which is still utter garbage. Why do I own a mac you ask? Because I got it for free from college when I graduated. And with the stupid prices they sell these things at their is really no reason for me to get rid of it.

  7. #7 Greg Laden
    January 28, 2015

    Paul, some of what you say makes sense, some of it does not. Please don’t use the word “retard,” that is obnoxious. But, thank you for your insight.

  8. #8 Rich Miller
    Chicago Area, IL USA
    June 24, 2015

    I can think of a few good reasons to turn off services– first and foremost– security. Particularly in the enterprise. And when you’re enterprise has dealings with PHI, you– the company– have an obligation to ensure to your clients and to your investors. They want to see that you are taking responsible measures to turn off “ways out”. In this case, I would want all iCloud functions turned off. I don’t want files synchronized to a server, I would prefer if people didn’t decide to register their devices to their personal iCloud services as they did not purchase the hardware. We do not like users who put their own kill switches on their computers.

    I am continually convinced and proven that Apple is not actually interested in innovating in OS X any longer. I have proven that OS X 10.6 far exceeds speed capabilities of any system following it and I believe that a lot of it has to do with iCloud enablement. If given the choice, I would rather have the speed than the “cloud integration” experience for my Mac.

    There are good things about Mac OS. And there are plenty of reasons to be using the platform. But the heyday in my opinion was during OS X 10.6. Everything since then has been a slower, glossier, re-packaged version of 10.7.

    So I would like to know how to turn off unneeded services that lead to unneeded processes, network bandwidth, CPU utilization, memory consumption, and security risks.

  9. #9 securityGUY
    October 16, 2015

    Most people here simply fail to understand security issues.

    From a security perspective too many file running in the background (that are not needed) are simply a security risk. Disabling all non essential functions helps with internet security. You have too many shared libraries and “cash” files that store information that can very easily be accessed when you go on line and download a file. Even a simple pdf file imposes series security risks without you even knowing it. The totally useless “widgets, are also always running and they are a problem. Access to your address book is very simple, as with many other items. Safari is possibly one of the most disgustingly disturbing program, that make and stores ever page and information in many different areas, that are NOT cleared, are removed unless you know how to find invisible files. Even Onex does not fully remove all the internet stuff Safari stores.

    So lets be realistic if someone understands this and really wants to be helpful the should cut the crap, and post simple commands, or direct someone to files that should NOT be on your system, one of them for example is the 4GB plus sleep image, that stores everything. And the other shared libraries that SHOULD BE REMOVED or at lease limited.

  10. #10 3Dhendo
    May 18, 2016

    This is overall a very good piece but I don’t entirely agree. There are several excellent reasons to disable services:
    1. Power. If, like me, you run pen testing tools then you do need every bit of RAM and CPU. You really do. Obvs there are better OS to use but you still might want to scan ports, run hashes or try to crack wifi on a Mac. So a process like mdworker which uses 17.5 of my CPU needs to be killed.
    2. Security. If you don’t believe me there is an excellent white paper by the NSA about how to harden OSX – disabling unnecessary services is high up there. It even recommends you disable WiFi and Bluetooth when not in use.
    3. It doesn’t matter. By all means warn people, but if I pay 2k for a laptop then I can do with it what I want. I can install/disable/add/remove whatever I choose. If I ask “what is the best way to spread vegemite on my screen?” then by all means say it’s a bad plan, but once that’s out of the way maybe suggest warming it up and using a plastering trowel. If someone asks a question it should be answered. We should not make moral decisions or tell people what to do unless they ask us directly.
    4. It’s not about Win vs Mac. Making these things a Win/Mac argument isn’t helpful and just serves to mame divides. I use Win, Mac and about 3 diff Linux distros and they are all great for diff things. It’s not about better. It’s about answering a question.

  11. #11 3Dhendo
    May 18, 2016

    if you really want to see a difference then I would suggest double/ triple booting your machine and perf testing the shizzle out of it. Get a Win OS, a Mac and a Linux.
    I boot into Kali to run more intensive tasks and it absolutely flies. Quad core CPU and 16GB RAM running on a Linux distro is way more efficient than Win or Mac OS. Of course it is – Win for e.g. is loaded with animations, fades, opacity effects etc. When I got Win7 I spent a day in regedit turning all that jazz off and there was a huge performance increase. Mac is no different – all those shiny visual effects aren’t free.

  12. #12 Greg Laden
    May 18, 2016

    I’m planning to build a new Linux machine. Basically, I’ll take my existing machine and replace the motherboard, processor, ram. I already have an SSD and a large regular hard drive, and all the other parts. (Not sure yet about the graphics card(s), and ultimately I’d like better monitors)

    I plan to get a motherboard that allows for a large amount of RAM, and fill it. I’ll get the fastest super duper processor that fits the budget.

    I have some tasks that involve a lot of data where the best way to handle the data is to assume it (and its derivatives) will all be sitting in RAM, but needing probably less than 12 gigs max. So, I can probably run those analyses and check my facebook page and make funny memes with gimp at the same time. Quietly. I’ve got a super quiet case.

  13. #13 Michael Medley
    March 9, 2017

    Sometimes when my Macbook starts overheating, I look at Activity Monitor and see a browser-related process taking about 100% of CPU. In particular, I keep seeing a process called “XXXXXXXXXX”, despite having long since closed the tab in which I viewed that page, and re-opened Safari and my computer. So how does one root out a clearly unwanted process like that?


  14. #14 Sunil
    TVM , India
    March 19, 2017

    Are there specific steps to disable automatic updates of AutoCad 2013 in OsX Sierra !!