As of late I'm noticing my Mac Mini running quite hot. When I open Activity Monitor I notice UVFSService constantly using practically 100% CPU (see screenshot below).
I'm running macOS Monterey 12.1
Mac mini, macOS 12.0
It's part of the system and all I could find is this:
UVFS is a pseudo file system that sends file system requests such as read and write system calls to user-level file system daemons.
Give this a try: boot into Safe Mode according to How to use safe mode on your Mac and test to see if the problem persists. Reboot normally and test again.
NOTE: Safe Mode boot can take up to 3 - 5 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files
It's part of the system and all I could find is this:
UVFS is a pseudo file system that sends file system requests such as read and write system calls to user-level file system daemons.
Give this a try: boot into Safe Mode according to How to use safe mode on your Mac and test to see if the problem persists. Reboot normally and test again.
NOTE: Safe Mode boot can take up to 3 - 5 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files
It looks like my issue is finally solved!
While updating my OS to macOS Monterey 12.3 (I had some lower version of Monterey — probably 12.2) it seems the updater corrupted something, and macOS was no longer able to load (it froze on the loading screen). I couldn't even access the Recovery tools as it froze on the "Analyzing disks" step. In the end I had to wipe the drive and reinstall macOS from scratch before restoring my latest Time Machine backup.
I don't know if it was the OS update that fixed it, or reinstalling the OS from scratch, but everything seems good now and I no longer see the UVFSService hogging the CPU... in fact there is no UVFSService! Did they remove it since 12.3?
First, there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac. This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community.
There are no known viruses, i.e. self propagating, for Macs. There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.
Anti Virus developers try to group all types as viruses into their ad campaigns of fear. They do a poor job of the detecting and isolating the adware and malware. Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.
There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is desshoigned solely to seek out adware and known malware and remove it. The free version is more than adequate for most users.
Also, unless you're using a true VPN tunnel, such as between you and your employer, school or bank's servers, they are useless from a privacy standpoint. Read these two articles: Public VPN's are anything but private and Former Malware Distributor Kape Technologies Now Owns ExpressVPN, CyberGhost, Private Internet Access, Zenmate, and a Collection of VPN “Review” Websites.
That being said uninstall CleanMyMac according to the developer's instructions. As far as your VPN app is concerned, if you're not required to use one by your employer, bank or school, I recommend you uninstall is accordingly.
Thanks for all the feedback.
I had uninstalled CleanMyMac several years ago (I suspect that back then I quickly realised that it wasn't so legit). What EtreCheck detected was CleanMyMac's LaunchDaemon which was somehow left over. I removed it. No other traces of CleanMyMac were found and EtreCheck is no longer detecting it.
I honestly have no idea how the system security got disabled, but I re-enabled it as soon as the EtreCheck report pointed it out.
I attached the latest EtreCheckPro report that I ran after the aforementioned changes. Needless to say, UVFSService is still consuming excessive CPU resources.
One thing I tried just now was to boot up the Mac with the external drive (used for Time Machine backups) disconnected. Still high CPU.
I decided to have a look at the Console logs. When I record console messages, there's nothing coming from UVFSService. I'm including the errors and faults in case there might be something relevant:
Also, the "Diagnostics Reports" tab provides a diagnostic report for UVFSService:
I see it includes the "heaviest stack" for the process, but it looks rather cryptic — to me, anyway. I guess it might prove insightful to someone familiar with the source code (which is probably hard to come by 😶).
It could be normal since it appears to occur right after upgrading to Monterey/restoring from ™ backup. After doing these things the the os has to do cleanup and other things.
Ithe % CPU apis referenced to i CPU core so % CPU can exceed 100% and does, part of normal operation,exceed 100. SO a process being near 100% is not unusual.
If this persists for 12 hours then download and run this app so we can find more information about your installation.
It shows what is launched and other information and is very useful in finding causes of problems. After you first launch the app make sure you check Enable full disk access in the box in lower left.
After running the app use the app's feature to paste to clipboard. Then paste it in the text box for a reply in this forum click on the addition text icon. This is because the normal reply text box limits how much you can type.
No personal identifiable information is contained if the app output. The app was written for a person who is contributor to these Apple Support Communities
@Alfabaco unfortunately I still haven't found a solution other than just quitting UVFSService 😕
I boot up in safe mode and opened the Activity Monitor, and immediately UVFSService ramped up to 100%.
What I find interesting, though, is that I can terminate UVFSService with no apparent consequences, other than CPU usage going down. Everything still works as far as I can tell 🤔. I don't want to be doing that each time after switching on my Mac, though.
I really don't want to reinstall macOS, but I'm wondering if there's any hope that restoring my system from my latest Time Machine backup might resolve the problem, or is it always just going to bring the system to the exact same state it was in at the time of the backup - warts and all?
Hi, since your last reply did you find any fix?
I'm currently facing the same problem on my MBP 16 2020, although it doesn't occur with the same frequency you described. The process kicks in unpredictably but frequently (almost every day) and keeps hogging cpu resources for hours until it stops.
I never installed programs such as cleanmymac, I only have installed bitdefender virus scanner but it doesn't run in background; as far as I know it doesn't "have" a deamon; and I let it run to check for malwares only once in a while (monthly circa). Also, I did some research before installing it and the program looks legit. I would doubt it has anything to do with the UVFSService process.
Bitdefender is still an unnecessary bit of software. It does nothing in the way of protection and can only hinder system and application performance. Uninstall it according to the developer's instructions.
After letting it run for about a day and a half, it's still consuming almost 100% CPU.
Attached is my EtreCheckPro report.
I reinstalled macOS and restored my latest Time Machine backup. Unfortunately, I'm still seeing UVFSService going up to nearly 100% CPU immediately after booting up 😕
You are injuring your mac by disabling system security and installing **** such as cleanmymac, which is tantamount to malware.
UVFSService constantly hogging CPU
