Have high cpu for kernel_tasks (min 60% all the time) after my iMac wakes up from a sleep. And it can be "fixed" only by reboot until next time when it is going to a sleep. I checked temperature and it looked normal, not exceeding 45C . So far disabled the sleep mode for the iMac but maybe there is a better solution for that.
At the least then, please reset the NVRAM and also please restart in Safe Mode. You can find instructions to each in:
https://support.apple.com/en-us/HT204063
https://support.apple.com/en-us/HT201262 (this may take up to 10 minutes.
Unfortunately you have not provided us with any useful information please do the following.
Please navigate to the Mac App Store and download the free version of EtreCheck OR please click www.EtreCheck.com where you will find the app. Once you downloaded the free app and created the report please post it as your reply to this message. In
order to post it, please use the following link for more detailed instructions on how to correctly include the results:
https://discussions.apple.com/docs/DOC-250000211
We can then look for obvious issues that may be causing your problem.
Nothing in your EtreCheck report indicates any issues. I would recommend learning how to use Activity Monitor to see what processes are creating the high CPU times. I suspect they may be due to outdated applications installed on the computer. If you have never used Activity Monitor please refer to: https://support.apple.com/en-us/HT201464
AM would only point to what process is using the high CPU. Are you having performance issues or are you simply curious? BTW, many experienced users gave up on putting the computer to sleep years ago. I simply put my display to sleep which has the same effect, this is what I'd recommend doing. You would set that up in System Preferences - Energy Saver.
Thank you for your response but I am not sure if it can help. The top process in the top or in the activity monitor after waking up is the "kernel_tasks" even nothing else is running. It happens only if the machine has gone to sleep and wakes up after that. How could Activity monitor to help with it? Maybe I am missing something.
I have performance issues every time when my computer wakes up from the sleep. It was working perfectly well until recent time and on one day I noticed that performance was really bad and my cpu is shown busy by 65% all the time. Yes, I know I can live without putting the machine to sleep but I would rather have it fixed if it is possible.
Here is the report.
Have high cpu for kernel_tasks after my iMac wakes up from a sleep.
