Slow iMac / Unknown Processes Using Lots of CPU

I spoke too soon, sadly.

While a clean install and reinstalling most 'Documents' (word processor documents, photos, a few videos, songs, etc.) and a couple config files (bookmarks, keychains) without any Applications or whatever else might hold the system down helped, as did removing iDrive entirely (whose customer support has been, shall we say, lacking), not all the system slowing has resolved.

Just yesterday, when nothing was especially taking up CPU use, a simple word search in the Finder brought up the Spinning Wait Cursor (aka, the 'rainbow pinwheel', the 'rainbow beachball', or the Spinning Beach Ball of Death) for several seconds before completing. I noticed it when I searched the word 'keychain', and a few minutes later when I test searched the common word 'book' to see how it behaved. I tried to replicate it later so I could get it on video, but by then it had passed.

This mostly seems strange to me because this machine has more RAM, and far less content on the disk to go through, than my 2014 iMac did. I can't imagine what's going on with memory management such that a machine with 64GB of RAM and only 170GB out of 2TB filled would have this issue.

Hi rccharles,

I don't see a way to edit posts, so I'll reply to the Activity Monitor here:

All the information you mention about Activity Monitor I already have and use, thank you. :) It's just that some of my earlier EtreCheck reports were quoting CPU usage percentages that didn't seem to be due to a small number of processes, so I couldn't easily figure out which ones were the culprits by process of elimination. A combination of a Pro account and numbers that were easier to compare 1:1 in Activity Monitor made it clear that one of the big contributors to the CPU and RAM use is pmset, which is system software.

Robert,

A couple of questions for you:

These apps are obsolete. There is recommended replacement for Silverlight.

Flash Player: 32.0.0.453 (? - installed 2020-11-10)

Silverlight: 5.1.41212.0 (? - installed 2016-03-25)

Question 1: What app is the recommended replacement for Silverlight? (I assume this is what you mean, and not simply, 'Apple recommends you remove Silverlight'. )

The Flash Player I have is their most recent version, 32.0.0.453 from 11/10/2020, so that's pretty recent. I know it becomes obsolete after December 2020, but for now I believe I need it for work. (I know.)

Question 2: Any idea why I can't click on my own EtreCheck report that I pasted above and view it? It seems strange that I would get 'file incomplete' errors, especially since you can look at it perfectly fine.

John,

I understand you identified pmset as one of the runaway processes.

Reset both NVRAM and SMC:

Reset NVRAM or PRAM on your Mac - Apple Support

How to reset the SMC of your Mac - Apple Support

I have done so. No change according to activity Monitor or EtreCheck. Within a minute of reboot after having done both, pmset was at 99.27%.

John,

Re pmset and EtreCheck: More to the point, pmset seems to be peaking only when EtreCheck runs. In other words, it's probably not the culprit of any ongoing slowing. Either way, I'll likely be backing up and reinstalling the OS today, as a last ditch method to have the machine be more functional.

Re: returning it . . .

You know, at this point I'd be inclined to contact Apple and tell them to take it back. You don't want it. At the very least that is certain to get their attention. The lack of interest you described is unacceptable. 


Take the cash and immediately buy another one just like it.

Apple made it clear in no uncertain terms that the fourteen day Buyer's Remorse period (which is not what you're referencing, I know) ended in three days -- they start that period from when you purchase, regardless of how long transit takes -- and that if I wanted another machine just like it, that was my only recourse. Even if I make it clear that the machine is not suitable for the purpose, something I'm increasingly suspecting is the case, a friend who has helped train Apple Customer Support made it clear to me that the best they'd likely offer me is a refurbished model that's 'equivalent in performance'.

Besides, demanding they take their machine back and refund you the money often only works when they perceive the customer voice as male. At least, IME.

John,

To elaborate/clarify:

The first Apple rep I spoke to told me that my Buyer's Remorse period ended three days from when I received the machine because the Buyer's Remorse period begins upon date of purchase, not date of receipt.

I've only had the machine a week, and it's only been clear that there were prevalent issues in the past handful of days, after the Buyer's Remorse period ended, if that first Tier II Apple Rep was correct. The only reason she even mentioned the Buyer's Remorse period was because I was unhappy that I couldn't downgrade to Mojave, and had been told by a different Apple Rep (probably someone at a store; I genuinely don't remember) that I could if I set up a bootable USB drive and followed certain steps. (That used to be true in for iMacs in the first half of 2020, but not the late-2020 iMacs.)

After I had two Apple reps tell me two different things about their Buyer's Remorse policy -- one saying even online purchases only had Buyer's Remorse until 14 days from purchase which could be lost mostly in transit, and the other one saying they thought the Buyer's Remorse policy for online purchases started when you receive the machine -- I looked it up myself. (This was in part due to you, 'John Galt', so thank you.)

And lucky me, I bought it over the holidays. According to their recently updated page, "Items purchased at the Apple Online Store that are received between 10 November and 25 December 2020 may be returned up to 8 January 2021." https://www.apple.com/shop/help/returns_refund

I am, however, going to give this one more shot. I've finally found a Tier II rep who seems to be willing to work with me, at least to the point of logging the errors, doing some remote diagnostic testing, and assisting me in my final 'nuke it from orbit' solution: wipe and clean install Catalina, and then manually install only files that shouldn't be causing the computer any issues if Disk Utility is accurate that there's no file corruption (Pages documents, photos, music, etc.). In most cases, I won't even bring over apps.

If I still have the problem? It's 100% time to replace it.

Hi John*, Robert,

I realize this is a reply technically to one of your comments, but essentially an update for both of you, and any/all who may read the thread. This is Part I of II.

After a try or two -- long story and not worth the text -- I lucked out and got a Tier II Apple Advisor who shares some common traits with me (a midlife Mac user who has used Macs for years), who both uses the Primary Offender app causing me issues (i.e.: the game I play, though he plays a console client version) and is a Mac App dev hobbyist.

He has taken responsibility for my support ticket, and seems to be of the I Will Spend Whatever Time Is Available And Reasonable To Help You Figure This Out school of IT support. He's doing this in part because I've had multiple issues with a Mac this new, including:

• the slowing I've mentioned previously
• some surreal audio issues where any file (local or remote) I play for more than 10-15 minutes can have a subtle but clear drop-off in quality, sounding like a flat and tinny sound source with a brief underlying 'buzz' in certain pitches or registers and/or a brief, intermittent audio 'stutter' . . . and more importantly, fixes itself if I force Quit the CoreAudiod process and essentially force it to restart. (It's 'worst' in external speakers, mildly better in headset via audio jack, and slightly better still in headset with USB - which uses different hardware and software stack than headphone jack does, I found out)
• the repeated massive (and often fatal) errors that occur when just beginning or while running cinematics in a particular game, including

1. 1. a game freeze that froze the entire system and forced a soft reboot; the later crash log (though this is an abort rather than a crash) indicated that it caused a SIGABRT (an abort due to an exception) to WindowServer [233] (!!!) (Hooray, apps passing bad data to system routines . . .) Apparently it was due to 'AMD transaction hang or work overload (AMD IOFB)’
   2. The graphics issue detailed in the above referenced Apple Support post
   3. A very loud *POP* noise in the middle of a cutscene, after which all system sound cut out (though I interestingly learned I could still hear via headset) . . . and upon quitting the app (a few minutes later), another *POP* noise and sound restored; the later crash log indicated three crashes at that time: of MTLCompilerService 11118, 11119, & 11120. (In case it's not known, MTLCompilerService is a GPU compiler that compiles a machine-agnostic version of Apple’s shader language for 3D rendering into GPU code that runs on the GPU in your device, with its current settings.) It says what's 'responsible' is Google Chrome Helper (GPU), of all things, and listed it as a EXC_BAD_ACCESS (SIGSEGV).

*- Nope, still haven't gotten used to seeing the name an Atlas Shrugged character here

Hi John, Robert,

Here's Part II of II.

I would share more about the crash logs . . . but unfortunately, they're gone, since resetting NVRAM completely wipes them out. I don't even have them for the Apple engineers anymore, just EtreCheck reports which miiiight reference them. I'd recommend giving a heads-up on this, in case folks recommend that in the future?

Given all this, what the rep and I opted to do -- after running an Apple Hardware Test and coming up with nothing, and since I'd already run the Heaven benchmark overnight without the machine keeling over -- was do Operation Nuke (Most Of) It From Orbit. Essentially a wipe, reinstall of Catalina, and then a careful manual reselection of only the Time Machine files that I know I'd want to keep: a lot of old but simple documents, pictures, music, a few videos, and some rare support files like browser bookmarks and a keychain. But no apps, no old 32-bit stuff, none of that.

Believe it or not, all that together took . . . 10 hours spent with the rep (which also involved explaining the whole situation, doing some of the above testing that wasn't the benchmark, a couple errors that sometimes crop up along the way . . .), and an additional 2-3 hours spent on my own on the things I absolutely knew I could do myself. Yee-ikes.

But the good news is that I now have a functional Catalina Time Machine backup. All the apps I'm running are either native or freshly downloaded except for one, which is very recent and needed to be manually reinstalled due to product key issues. Assuming this machine is fixable, or I get a new one like it, this will make things a lot easier down the road.

Having done that, the machine is admittedly is a fair bit faster. Not as fast as I would have expected a 2020 iMac with an SSD and 64GB of memory to be, but it's improved. And I don't think I've seen pmset pop back up as a high CPU item.

I've also just ran EtreCheck, and there are no more major issues. The minor ones involve, like, one orphan file, and a couple support files that were brought over from the one app I had to manually reinstall, because the Apple Rep wasn't sure I wouldn't need to bring it along to make it work. Google Chrome Renderer is using a fair bit of RAM (~20GB), but that's often standard operating procedure for Chrome, unfortunately, especially if you tend to keep a lot of tabs open.

However.

The machine still has that surreal audio issue, which alone makes me tempted to give it the boot (sound/music is important to me), and those issues with That One App.

But the good news is that I have a good bit of time. The Apple Rep is going to be sending a report to the engineers first thing tomorrow about the audio issue, and I've been told that some more testing of the Problematic But Fun App is a good idea in the meantime.  

Guess I'll just have to game a little more. Apple told me so.