Become a MacRumors Supporter for $25/year with no ads, private forums, and more!

kernel_task taking up a lot of memory?


macrumors regular
Original poster
Nov 8, 2010
Atlanta, GA
Hi everyone,

Earlier today I called in Apple support because of a problem I had using spotlight search. It wouldn't show any of my applications or documents in the search results, with the Indexing... bar going on forever. The very kind customer service rep walked me through doing a NV RAM reset.

I am now able to see my applications and documents show up through a spotlight search, however the indexing bar is still on and won't go away. After the reset, the service rep looked at my activity monitor, noticing that kernel_task was taking up about 1.5gb of my memory. He told me that is not normal, and insisted I reinstall Mac OS.

I'm now having to backup my files (of approximately 800gb) through time machine which will take up my whole day, and wanted to ask the Mac Pro community if you had problems with the kernel_task taking up a lot of memory and any other problems with spotlight.

Do you guys think a OS reinstall is necessary to fix this issue? This problem came up just very recently (maybe 2 days ago) and the only 'change' that my Mac Pro went through is the usual App Store Updates and a Windows 10 installation 4 days ago through Bootcamp. Would the boot camp cause these problems?


macrumors G5
Apr 3, 2014
Hong Kong
I don't know what's wrong with just 1.5GB, especially your Mac is busing with indexing.

I just boot my Mac ~30min ago. And Kernel_task take more than 2GB. The memory consumption usually vary between 2-3GB (most of the time stay at around 2.5GB).
Screen Shot 2017-04-20 at 00.37.46 copy.jpg

By considering you have 800GB data, the indexing can easily require for few hours. If you want to make sure the indexing is a clean new process, you can restart it by opening system preference -> spotlight -> privacy. Drag all hard drive into the list. Then the indexing should be stooped and all indexing data is cleared

At this point, spotlight should not able to search anything for you. Once you confirm the index is clean. You can then remove everything from the list. The spotlight indexing will start again. Just leave it overnight, or let it run for few hours (you can keep using your Mac, but just spotlight is not ready yet).
  • Like
Reactions: Weaselboy


Staff member
Jan 23, 2005
I agree. Nothing really wrong with 1.5GB being used. Just give it time to settle down and complete the indexing.


macrumors 68040
Aug 28, 2012
Between the coasts
1.5 GB for kernel_task doesn't seem high to me. Mine is running at over 3.2 GB at the moment - it's been quite a while since I last restarted, and usage tends to grow over time.

Take a look at CPU usage in Activity Monitor. If kernel_task is using a high percentage of the CPU (like 90% or more), then there may be an issue - see this Apple support article: (my kernel_task is currently running at about 7% CPU).

Your Spotlight could have started reindexing after you created the Windows partition, and with over 800 GB of files, reindexing may take several days.

I'm not sure a reinstall will help, as I don't think there's anything obviously wrong.


macrumors G5
Apr 3, 2014
Hong Kong
Yes, spotlight will index the bootcamp partition as well. That may be the trigger of the new indexing. I indeed put the whole Windows SSD into that privacy list. I don't need spotlight show me the Windows file when I am using MacOS. And I don't want MacOS touch the Windows partition actually.


macrumors 601
Sep 15, 2006
New York City, NY
As everyone else here has stated 1.5GB is not much at all. Mine is using 3.5GB. Installing Windows should not affect this.

macOS uses lots of RAM. As long as swap memory is not absurdly high, it should be fine.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.