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Mohave degrade performance for non-active application - MacBook Pro 2018

Ever since I got my new MacBook Pro with Mohave, I noticed a degrade in performance of certain apps. The most notable app is VirtuaBox VM. A task that took 6 mins to finish now takes over 25 mins unless I actively have the VM selected. This happens when connected to the power adapter or running on the battery. There seems to be a change in the OS that degrades the performance for apps that aren't active.


Is there any way to tell the OS to never degrade performance of certain applications?? I don't mind turning off the feature all together as well.

MacBook Pro with Touch Bar

Posted on Apr 2, 2019 12:17 PM

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Posted on Apr 24, 2019 3:13 PM

I finally figured out why this was happening. Apparently, it's caused by the App Nap feature that Apple introduced back in 2013. It's responsible for degrading performance of apps that are not active.


I found that if I disable the App Nap feature all together, start VirtualBox and reenable it again, my VM runs at full performance, even when minimized. It works like my previous MacbBook.


I wish there was a way to disable App Nap per application. Unfortunately when I open the info page for the VirtualBox app, it doesn't have the option to Prevent App Nap. I'm not sure if this option is even available anymore.

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Question marked as Top-ranking reply

Apr 24, 2019 3:13 PM in response to ryanatsinew

I finally figured out why this was happening. Apparently, it's caused by the App Nap feature that Apple introduced back in 2013. It's responsible for degrading performance of apps that are not active.


I found that if I disable the App Nap feature all together, start VirtualBox and reenable it again, my VM runs at full performance, even when minimized. It works like my previous MacbBook.


I wish there was a way to disable App Nap per application. Unfortunately when I open the info page for the VirtualBox app, it doesn't have the option to Prevent App Nap. I'm not sure if this option is even available anymore.

Apr 3, 2019 4:59 PM in response to ryanatsinew

I suggest you use the program created by Etresoft, a frequent contributor.  It will provide a snapshot of your system which we can analyze to possibly determine the cause of your problem. Please use copy and paste as screen shots can be hard to read. On the screen with Options, please open Options and check the bottom 2 boxes before running. Click “Share Report” button in the toolbar, select “Copy to Clipboard” and then paste into a reply. This will show what is running on your computer. No personal information is shown.


  


https://itunes.apple.com/us/app/etrecheck/id1423715984?mt=12




Use the Add Text button to include the Etrecheck report in your reply.

Apr 3, 2019 5:04 PM in response to Teddy_B

Thanks for your response Jameson. My MacBook Pro is not running slowly. It works great as long as you have the VirtuaBox window active. In fact, the same task runs twice as fast on the new MacBook Pro (Mojave) than my previous MacBook Pro (High Sierra). Again, the window just has to be active. If it's not active, it runs 4 to 5 times slower. There seems to be a change in the OS to reduce the resource use of application running in the background.


I'm in the process of upgrading my previous laptop to Mojave to see if it's OS related or the new MacBook Pro.

Apr 4, 2019 7:49 AM in response to ryanatsinew

I finished upgrading the previous MacBook Pro to Mojave and it still runs consistently whether the application window is active or not active. It looks like the issue is isolated to the new MacBook Pro 2018. I ran the task 2 more times this morning. As you can see below, it took over 18 mins when the window was not active and less than 4 mins when it is active.


Importing J2EE module tools.war declared in UGP.Tools

Parsing /AE/deployments/aeoaux.ear/tools.war/WEB-INF/web.xml

Assembly took 2.7 seconds.


BUILD SUCCESSFUL


Total time: 3 mins 52.249 secs



Importing J2EE module tools.war declared in UGP.Tools

Parsing /AE/deployments/aeoaux.ear/tools.war/WEB-INF/web.xml

Assembly took 5.334 seconds.


BUILD SUCCESSFUL


Total time: 18 mins 35.089 secs

Mohave degrade performance for non-active application - MacBook Pro 2018

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