My 2012 MacBook Pro apparently has a runaway process that's using 99.7% of the CPU according to the EtreC
heck report. However I don't notice any performance issues or slowness; Activity Monitor shows kernel_task using a large number of threads and idle wake ups. Any suggestions on how to remedy this?
I don't see anything specific in the report although there is one or two apps that I'm not familiar with though.
I see you are using DriveDX. Post the DriveDx health report here using the "Additional Text" icon which looks like a piece of paper.
You do have the 13" model so there is a possibility the hard drive SATA Cable is bad. This cable has an extremely high rate of failure on this specific model especially when using an SSD. You can remove the SSD and connect it externally using a USB to SATA Adapter, drive dock, or enclosure to see if you have the same issues while booting the SSD externally. If it works fine booting the SSD externally, then the internal hard drive SATA Cable is most likely bad.
Also run Disk Utility First Aid on the hidden Container. Within Disk Utility click on "View" and select "Show All Devices" so that the hidden Container appears on the left pane of Disk Utility. Even if First Aid show everything is "Ok" click "Show Details" and look through the report to see if there are any unfixed errors listed. If there are any unfixed errors listed, then you will need to erase the whole physical drive before restoring from a backup or clone.
Do you have the same issue when booted into Safe Mode?
The Mac App Store version of EtreCheck cannot directly see some system processes. You will have to use Activity Monitor for these. Make sure to go to the “View” menu in Activity Monitor and set it to view “All Processes”.
Also, EtreCheck is just a snapshot in time. There is no guarantee that Activity Monitor is going to show the same activity. Processes start up and shut down regularly.
The issue was even worse in Safe Mode; Other processes was over 200%. First Aid showed everything OK with no unfixed errors.
I attached the DriveDX report.
You only pasted the path to the report. You need to copy & paste the report into the "Additional Text" feature.