Speeding up Chrome on Macs

Speeding up Chrome on Macs

Summary: Chrome is one of the fastest Web browsers around, but on Mac OS X it can get really, really slow. Here are two ways to restore its speed.

Chrome on Mac
To keep Chrome working at speed on a Mac often requires a bit of work.

Google's Chrome is my favorite Web browser on any platform. On Macs, though, I've noticed that it has a tendency to get really, really slow over time. I checked into this and I've found two common reasons for this and their solutions.

1) Adobe Flash crashes and slow performance

The first problem actually springs from one of Chrome's features. Chrome comes with Adobe Flash built into the browser so you don't need to download it. But, say you use another browser, such as Safari or Firefox, on the same Mac, guess what happens? That's right, you end up with a downloaded copy of Flash and Chrome's native Flash player.

The immediate result is Chrome will run slower. You will also start to see Flash crashes in the browser as the browser grows increasing confused about which version of Flash to call.

To find out if this is the root of your Chrome/Flash problems, go to the Chrome browser's address bar and type:


And hit enter. You'll see a a list of all installed plug-ins. Look through it for the Adobe Flash Player entry. If the entry says Chrome has 2 Flash files, congratulations, you've found the source of your Flash problem.

 Next, click on the Details button on the top right of the display. This will show you more information about your plugins. Head down the list and look at the Flash Player descriptions closely and look at their Types. The one you want to shutdown is the that's labeled NPAPI (Netscape Plugin Application Programming Interface). This is the non-Chrome version of Flash. Click on the Disable link for it and then close and restart Chrome. All should be well now.

If you have two copies of Flash in Chrome, you need to disable the one labelled NPAPI.

As a general rule, you don't ever want to run NPAPI-enabled plugins on Chrome. They are designed to run with the current user's full permissions and Chrome doesn't sandbox or shield them from malicious input. In short, if you find a NPAPI plugin in your Chrome plugin list, disable it. It's a potential security hole.

2) General slowness

The next problem springs from what I think is a real Chrome annoyance: Chrome keeps everything in the world—Web pages, cookies, Web history—in its cache.

So far, so good, on Windows and Linux PCs. On Macs though, Chrome tries to keep as much of its cache as it can in memory. How much? All of it. What happens when you run out of free memory? You run into a problem called thrashing. Out of RAM, your Mac starts going to virtual memory, aka your hard drive, for process storage and just like that your Mac moves from working at processor and memory nanosecond speeds to a drive's milliseconds speeds. Yuck!

Now if Google had its act together this wouldn't happen at all. Or, at the least Google would give you a way to adjust your cache's size. Say, for example, hold only 1 GB or 1 day of data. Other browsers do. There's no way to do this from Chrome's user interface.

You can set the cache size from the shell by running Chrome with the --disk-cache-size=x flag where x is the number of bytess you want to set aside for the cache. So, for example,


would set Chrome's maximum cache to 500MBs. Unfortunately, while that's easy to set up in Linux or Windows, there's no easy way to set this, or any other flag, on Mac OS X programs without using a shell script or AppleScript. Worse still, I've yet to find a shell program that will work consistently with Chrome updates and across different versions of Mac OS X.

So, I must recommend that you manually go and clean out the cache whenever you notice Chrome is getting slow. To do this do the following steps:

Click the Chrome menu on the top right of your browser toolbar.
1. Select Tools.
2. Select Clear browsing data.
3. In the dialog that appears, select the check-boxes for the types of information that you want to remove.

Oddly, you can't choose to get rid of the oldest data first, you only get choices to get rid of newer—past hour, day, week, or four weeks—data or all data. Personally, I'd want to get rid of the older stuff first. Since I'm blessed with a 100Mbps cable connection I just delete eveything. You'll get the biggest speed improvement with the least amount of effort by just choosing to empty the cache. If you hate cookies, you might as well delete them while you're at it.

4. Then, Click Clear browsing data.

Finally, close and restart the program and you should see an immediate and significant speed improvement.

For some reason, I only see these problems with Chrome on Mac OS X, Lion and Mountain Lion. I never see them on Windows XP, 7, or 8 or any version of Linux. But, if you're a Mac fan, and you love Chrome's speed—when it's behaving—this should make using Chrome enjoyable once again.

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Topics: Apple, Browser, Google, Networking, Software

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  • Where is the real SJVN?

    You actually got through a whole post where you mentioned Windows and not only did you not say anything bad about it, you actually highlighted a situation where Windows is better than something else. Are you feeling okay?

    Anyway, what a shame that these steps are required. This is not something we could expect 99.9% of ANY OS user base to accomplish but these steps simply aren't required on Windows (or Linux). I guess most people just have to live with slow Chrome on OS X. Too bad. This is the opposite of "It Just Works".
    • www.Google.MEL7.CoM

      Elizabeth. you think Jesus`s artlclee is flabbergasting... on friday I got a top of the range Citroën DS after having made $8812 this last month and in excess of $10k this past month. with-out any doubt it's the nicest-job I have ever done. I started this 3 months ago and pretty much immediately was earning at least $71 per-hr. I follow the details here...Above
    • Why would these steps be hard for a user?

      "This is not something we could expect 99.9% of ANY OS user base to accomplish”
      • not a question of how hard

        it's that these steps shouldn't be necessary at all. Cmon Google, you can - and should - do better.
    • He's being useful

      Perhaps you should give it a try, if you can manage it.
  • I love the CLI

    Too bad I don't have a Mac. Although, if I did, I'd likely use Firefox and Opera as I do on Windows and GNU/Linux.
    Rabid Howler Monkey
  • Did the Linux machine refuse to boot this morning

    Thats why you are on a Mac today?
    • --

      Off topic comment.
  • Curious

    Not one Apple fan posted a comment expressing how superior Safari is to all else, even though Apple fans are reputed to be hypersensitive to even the slightest criticism of Apple or its products.

    Now let's see what happens if SJVN writes a similar article about how to tweak Firefox or Chrome under Windows (*especially* if IE is never mentioned).
    John L. Ries
  • Screen Shot looks like...

    Screen Shot looks like Windows 3.1 with that old Norton UI add-on from 1993.
    Nole Mercy
  • Problem of slow Mac performance

    I prefer to use safari on my Mac. Its not not only the chrome which slow on my machine but other apps also face the issue and the whole Mac performance goes down.

    I remove the useless items like system ache, duplicate files, unnecessary apps with Mac cleaners. The Mac cleaning tool I have bought recently is Stellar Speed Up Mac and it really means its task.
  • Chrome rapide


    Merci pour ce post trés utile, en effet chrome est le plus rapide des navigateurs et il souffre sur Mac osX.Maintenant c'est plus clair. Information trés utile sur les NPAPI. Chacun a comme ça la liberté , d'user du server qui lui convient..SANS FANATISME.....
  • So why is Chrome so great?

    These problems seem typical to any browser? Slow Flash player or one that crashes, and a browser that slows down over time. But I see less of these problems with Chrome in Windows then I used to on a Mac. In fact I finally got rid of my Mac because I finally realized nothing but Apple stuff runs that great on a Mac. Not to say a Mac was not a really nice PC or that Mountain Lion was not a good OS. But it did seem like Apple kept making changes to its OS that kept the third party people scrambling to fix stuff. As far as Flash goes I use Firefox and IE 10 too and so with Chrome that makes for 3 Flash versions on a PC I use. The Active X version for IE, the one for Firefox and the built in Chrome one. I did always wonder if some conflicts could occur with this type of setup?
  • All NPAPI plugins?

    HI - Thanks for the post. I followed your instructions and noticed there are a significant number of NPAPI type of plugins but you said I should never run these. Some of them are built by Google (Google Talk for example) - Should I still disable these for performance?

  • Thank you! Great suggestions!

    I usually take this random tech advice and move on... These suggestions were so helpful, the instructions so clear and there is such a significant improvement in performance, I needed to register on the site simply to post this, THANK YOU!
    Eve Eriksson
  • You missed some points !!

    Well, you missed some points. Duplicate files, too many installed programs, volume fragmentation and temporary contents make your Mac run slower. Here is a complete guide: http://naumanlodhi.blogspot.in/2013/07/review-of-pc-keeper-by-kromtech-inc.html
  • Very useful, thank you!

    From the blogs I read about this topic this one was definitely was the most useful and practical. I also provided me with new practical knowledge about Chrome.