Sluggish Mac? Here’s what you can do about it

“One of the best things about a Mac is that they often last a long time,” Michael Potuck writes for 9to5Mac.

“While this is a great feature of a quality product, your Mac’s performance may also decrease the longer you own it,” Potuck writes. “And even if you have a new or relatively new Mac you’ll likely find some value in [these] tips.”

“We’re going to take a look at Activity Monitor which is built-in to macOS and provides a great way to check your Mac’s system resources and how it’s doing,” Potuck writes. “It can also give us some direction in improving performance.”

Potuck writes, “Another common thing that will slow down your Mac is your hard drive, particularly if it is a hard disk drive (HDD).”

Read more in the full article here.


  1. 1. By far the most important upgrade to a Mac is replacing an HDD with a SSD. Did that to my 2009 Mac Mini two years ago and it turned it into a new machine. No more spinning wheels and it still performs well as a media server.
    2. If you already have an SSD drive but it is smaller than you need then upgrading to a larger one will help. I am going to do that to my 1st gen rMBP (250GB to either 500 or 1000GB). Having the additional headspace prevents running out of space especially when needing to store important files for perpetuity. That machine will replace the 2009 Mac Mini as a media server and with the internal battery makes it impervious to power outages.
    3. RAM is the next important item. With older Macs, you can upgrade for cheaper. With new Macs, it is best to get the RAM you will need when you buy since you cannot upgrade.
    4. Finally a clean install is a good idea. I haven’t done one for years since there are always programs that I’ve lost the software key.

    1. Well Said here! I am using a Mid-2012 non-retina MacBook Pro that runs way faster than those 2+ years later… I put Samsung 850 Pro 512GB SSD and 16GB Crucial Ram, Cleaned out non english files with clean my mac, Run Onyx one a month. It Boots in 8 seconds and Runs like a bat out of hell with 2017 apps. Only down-side is low Video-Ram which never runs out anyways since I don’t play the big games.

      1. So glad to hear that, thanks! That’s the machine I have but I haven’t upgraded yet. Had read that 16GB was possible even though It’s not according to Apple.

        1. It should be possible. My machine is older than yours and I upgraded it to 16GB from
          Here’s the specs:
          Mac mini (Mid 2011)
          2,5 GHz Intel Core i5
          16 GB 1333 MHz DDR3
          AMD Radeon HD 6630M 256 MB

  2. What a a nagging insistence with the hard drive slowing down your Mac. If that were the case then why was it not slow when you first bought your Mac?

    Yes, the hard drive is [a lot] slow[er] as compared to a solid state drive and that’s a factor that makes your Mac go slow but, the reason it becomes slow is because programs take longer to read/write/find information as your hard drive fills up. Clean your hard drive out of stuff you no longer need, defragment it and you must see some performance improvement.

    1. This is really poor advice.

      As long as your Mac’s boot volume has twice the available free space as it has RAM, there won’t be a slow down as it fills up. Removing files below that threshold does nothing for speed.

      For example, if you have a Mac with 8GB of RAM, you should try to maintain at least 16GB of free space on your boot volume. However, you won’t see a significant speed difference between having 18GB and 180GB of free space on your boot volume. You’ll see articles claiming X% of drive space should be free, but that’s not really right either. That advice is given in terms of reducing fragmentation (more on that myth later) and on the idea that X% of a typical drive should correlate to Y% of RAM, which often isn’t the case.

      macOS also auto-defrags using a process known as HFC (Hot File Adaptive Clustering). This doesn’t keep drives defragmented 100%, but for the overwhelming majority of people defragging a hard drive is a waste of time (and potentially a risk for data). The rare exception for this would be those filling up drives with very large media files, and then deleting individual ones and filling it back up again without ever reformatting.

      With an SSD, fragmentation simply does not apply in the same way at all.

      The slow down of a Mac can be caused by a variety of factors. Everything from cat hair clogging up the fans to human perception of the Mac feeling slower even though it’s not. It can be cause by newer software consuming more resources as well as newer usage by the owner and an increase in background resource usage.

      Fragmentation or a boot volume full to less than double the amount of RAM, is extremely low on the list of likely slow-down culprits.

  3. Even with a newer Mac you can connect an SSD via USB 3 and designate it as the boot drive. One of my Macs at the house is a current model Mac mini with an SSD hooked up in that manner with the slow internal HD being the Time Machine backup. Should that Mac die, I can plug that SSD into any other Mac and use it as the boot drive.

    My Mac Pro tower has an SSD mounted in the empty second optical bay as the boot drive. The sled mounted HDs hold Music, Movies and TV. A Pro Box externally is a backup of all files- including the large Video library which serves via iTunes to my Apple TV.

    SSDs are dirt cheap, a USB 3 housing is cheaper still and you can easily use them as a boot drive that can swap between computers. Just remember to have a local PHYSICAL backup.

  4. Well Said here! I am using a Mid-2012 non-retina MacBook Pro that runs way faster than those 2+ years later… I put Samsung 850 Pro 512GB SSD and 16GB Crucial Ram, Cleaned out non english files with clean my mac, Run Onyx one a month. It Boots in 8 seconds and Runs like a bat out of hell with 2017 apps. Only down-side is low Video-Ram which never runs out anyways since I don’t play the big games.

    1. “Sluggish Mac? Here’s what you can do about it”

      Buy a PC instead, yeah, and then upgrade the hell out of it anyWAY you want and whenEVER the the hell you want. No pesky single choice Sir Jony Ives slim design to throttle your upgrading desires oxygen supply.

  5. I upgraded my old iMac with a Thunderbolt SSD drive. Very simple and no need to open the Mac.

    Boot time went from over 2 minutes to about 20 seconds max. Photoshop load in 15 seconds compared to nearly 3 minutes before the upgrade.

    Current iMacs are not worth the price, IMHO. At the very least they need a big SSD drive.

  6. I put a Seagate Hybrid 1TB SSD/HD into my 2010 MacBook Pro and it transformed the performance. It’s beginning to show it’s age in terms of processing power because it’s still slow when using iMovie and editing video off my GoPro. But then I have to remember it’s 4K video getting edited on a Core2 Duo with 4GB of RAM.

    I’ve not done a clean install since about 10.4, I just upgrade. Activity Monitor is a great tool to trim the fat after monitoring what’s going on for 5-10 minutes. I always amaze friends whave asked me to clean their Mac when I sit there with Activity Monitor running and then removing loads of crap (I took RealPlayer files off a Mac the other day!) Good places to look are inside /Library and ~/Library… my only advice is if you look in /System and decide something inside there needs removing, THOROUGHLY RESEARCH THE FILE. Look on Google, ask in forums… it’s a bad idea to mess around inside /System.

    I’ll be upgrading this year to a new Mac (can’t wait!) and putting this one up on eBay and I should get a good price for it based on what they are currently selling for. As others have said, I’ll max out the RAM at the time of purchase because most Macs now are non-upgradable in those areas which is a shame.

    7 years use for £1500.
    58p a day. Not bad.

  7. One word: SSD. Apple puts 5400 RPM (slow) drives is many of its products, so I find swapping over to any SSD makes a huge difference.

    Example: A friend had a Core2Duo Mac Mini Server (2009) 4GB RAM that he was ready to junk, so I upgraded it to an SSD. Feels like a brand new machine and runs El Capitan quite smoothly!

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