After macOS High Sierra upgrade I noticed "QuickLookUIService" is always in "Using Significant Energy" list. Has anyone have same problem? And is there any suggestion about this?

MacBook Pro (Retina, 15-inch, Mid 2014)

Version 10.13.1


  • This is normal to generate quick look thumbnails and process files in the background. Do you experience this after letting the machine run without sleep for several hours or overnight connected to power? – bmike Nov 25 '17 at 21:51
  • Yes. But I tried to restart and it's gone. I guess when I quick look something, it will stuck again. If it will not I will let you know. – musa Nov 26 '17 at 16:37
  • I have the exact same machine, but running Mojave, and I've seen this happen a few times. Most recently when I noticed this pop up, my battery dropped to 63% after 45 minutes of use, with nothing else open other than Safari. I don't know what causes it, but logging out and back in seemed to fix it. Just a process running haywire for whatever reason. – daGUY Apr 14 '19 at 15:31
  • @daGUY I installed gfxCardStatus app and getting notifications when mac switched graphic card. And I force quit the QuickLookUIService and it's returns back normal. – musa Apr 15 '19 at 21:36

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