iMac keeps crashing after Catalina upgrade

There are solutions, but they are several pages back, and they don't seem to work for everybody. Here's what I have surmised thus far, quoting my earlier reply.

"Looking through this discussion, I saw several potential solutions:

(a) Downgrade to Mojave or High Sierra;

(b) Get rid of any 32-bit software lurking deep in the system; and

(c) Switch off the sleep capabilities.

"Options (a) and (b) were clearly going to take some time, so I went for the 'switching off sleep' option, as a starting point.

"So far, no crashes. I have put the MBP to sleep manually and it has woken without any drama. Yes, it's only been about 15 hours now [updated the time], but I would have expected a couple by now, on a normal day. I started without external monitors, then added the two regular ones. It just handled it easily.

"Tomorrow morning I will know better. 24 hours will be a better test, and I will have it connected to a different pair of external monitors [I have already and no problems at all] and then a video projector. I'll let you know if there have been any crashes in that time."

Try the sleep option. The details are in a post about 3 pages back (about page 24 or 25 of this thread), and there are other details of the '32-bit software hunt' you can do, including how to do it and software that can help, and links to the downgrade option.

If the 'sleep' fix works, that's great. If not, keep it and try the '32-bit software hunt' option. There seem to be some drivers that are software specific that are still 32-bit hanging around, and often they are bit of code deep inside a large chunk that seems 64-bit. If that seems daunting or you've got too much stuff that you need that has 32-bit issues, go for the downgrade option.

Note that the file extension on Time Machine back-up files was changed with Catalina, so you will need to change that extension manually to access the back-up files with Catalina or Mojave. There are details of that in a post about 4-5 pages back.

I'm not sure that I have fixed it, but it may be a step in the right direction. Those who said that Adobe software had this 32-bit issue should note that some updates came out this afternoon (Thursday, 7th November, 2019) for the Creative Cloud apps (I think all 7 that I have installed noted that updates were available), so Adobe may be moving on the 32-bit issue.

Good luck with this, folks. Read back through the previous pages to see what solutions have been posted. There's 28 pages so far, so it may take. bit to see them all!

I can only suggest what has come up already in this rather long (31 pages to date!) thread. That seems to be:

(a) switch off sleep mode, but you can allow Power Nap to be on;

(b) switch off Time Machine back-ups (that seemed to trigger some crashes for me);

(c) go through your machine and find every last 32-bit app, driver, sub-driver, routine, and piece of code, and replace it (which is a pain, but an app called Go64 seems to do the search for you) or eliminate it;

(d) downgrade to Mojave or High Sierra.

I did (a) and it helped for about 24 hours, then (b) when the crashes returned. That reduced them, but didn't eliminate them, but that may be enough to get you rolling with (c) and/or (d). I'm going to look at (c) real soon, to see if there is anything obvious.

The crash logs I'm getting suggest two things. One is that something is hanging the system, and the 'watchdog' doesn't get called for a minute or two, and then the system has a panic. What causes the hang itself seems deeper. The other suggests some other kind of error and that is rarer, but it does seem to have occurred during boot once. I've even had the system stall and then crash as a result of trying to submit a crash report!

Whether this is a hardware issue seems uncertain. The behavior has a lot of similarities to an intermittent RAM error, but it probably isn't. Whether the software issues are causing hardware problems is also uncertain, as is the question of the hardware inducing a latent problem to become more apparent. If it is software causing hardware damage, we probably should be going back to Mojave as soon as possible.

I found that whatever I do seems to work for a while, then back come the crashes. Crashes do tend to cluster: get one and more follow until things stabilize.

I 'm hoping that Apple gets this one sorted out a.s.a.p, because this is a huge black mark for them. We are getting a lot of mixed messages here from Apple, and it isn't helping. It is digging into my productivity.

Same issue here but I may have fixed it (fingers crossed). Was crashing every 20-30 minutes after installing Catalina. Last night I did 3 things: ran disk first aid, reset SMC, zapped the PRAM then shut it down for the night. So far today have had no crashes at all. Computer has gone to sleep and awakened normally, I have left the computer and have had no "restarted because of problem" messages when I returned, no black multi-language error screens. Hoping this solved the problem.

iMac 27" late 2015

3.2 GHz Quad Core Intel Core i5

24GB 1867 MHz DDR3 (including 2 off-brand)

AMD Radeon R9 M390 2GB

cantlep wrote:

I'm running a late 2013 Mac Pro (trashcan) and also have had this issue every day (many reports submitted to Apple) since upgrading. However, yesterday, I upgraded to 10.15.2 (Beta) and for the first time since upgrading to Catalina, the machine didn't crash overnight. For those who are really suffering, it may be worth joining the Apple Beta program and seeing if it helps you too.

Apple Beta - https://beta.apple.com/sp/betaprogram/

Again, which problem did you have? There are lots of different issues and crashes in this thread.

mithos99 wrote:

Good news, guys!

It seems 10.15.2 beta2 fixed halt-restart-unattended-with-external-monitor issue.

My Macbook Pro 2018 Vega20 with two external monitors just turned them off and gone happily sleep after 30 min unattended and woke up without any errors.

Before 10.15.2 beta2 is was always panic-halt-restart with report to developers.

You should try 10.15.2 public beta2, guys.

I hope this keeps working for you!

Not to pee on the fire, but maybe give it a couple of days before getting excited. More for your own sanity than anything else 😃.

Maybe I found a solution.

I've tried nearly everything - changed RAM, reset anything, boot from internal and external drives, switched WLAN on and off, but nothing helped. There was one last thing to try - and now I can go to sleep mode and wake up my iMac without any problem. Maybe it's a little early to give the green light here, but switching of Bluetooth did the trick.

It took some time to find an old USB keyboard and mouse, but now everything works fine. I keep watching the next days, but could you please try and give feedback? Good luck!

mithos99 wrote:

Good news, guys!

It seems 10.15.2 beta2 fixed halt-restart-unattended-with-external-monitor issue.

My Macbook Pro 2018 Vega20 with two external monitors just turned them off and gone happily sleep after 30 min unattended and woke up without any errors.

Before 10.15.2 beta2 is was always panic-halt-restart with report to developers.

You should try 10.15.2 public beta2, guys.

So is this still stable for you?

Confirmed that my Catalina crashes directly correlate to using an external (extended desktop) connected by thunderbolt-- running on Mid 2015 MBP retina 15" 2.8 quadcore i7. Zero crashes when I disconnect extended desktop monitor(s). I eagerly await a fix for this pleassse.

Yes.

Since Beta2 10.15.2 I'm stable with my MacbookPro 2018 vega20 and two external monitors (via Thunerbolt3 and TypeC-DisplayPort connections).

So if your setup stops halt-reboot-when-idle when you disconnect external monitors, I would recommend Beta2 10.15.2. With all precautions - backups, offwork time etc.

Hope it helps.

Lawrence Kellogg wrote:

I’m an iOS developer and have been one for ten years. I’m not switching to another operating system. There are no utopias in the technology world, everybody has problems.

What things should I try to keep my machines from crashing all the time? Should I disconnect the second monitor before putting the machine to sleep? I certainly don’t want to work without a second monitor.

Try not starting the Music app, deleting (EDIT: or renaming if you don't have backups) [path_to_user]/Music/Music and resetting SMC and PRAM in that order. In my setup at least this solves the crashes (10.15.2 beta 2 / 3). I didn't try it under 10.15.1, but I suspect it would be the same story. I'm kinda sad to be without a Music app on my Mac, but working Mac seems more important.

Sorry to hear you have a similar issue with external monitor(s). Apparently, you are not alone in this.  

If after all PRAM, SMC resets, hardware diagnostics, and a fresh macOS Catalina install you did, your Mac still crashing, then it is definitely a high IO activity involved that it can’t be confirmed or seen in Activity Monitor utility alone.

To get a live look at the way your Mac performs and how the IO commence in real time, there is a special developer tool called IO Registry Explorer. This tool is used by developers to troubleshoot issues with any hardware or peripherals your Mac utilize and interacts with. You need to create a developer account to download Additional Tools from the developer site. After you download and install Additional Tools in the Utilities folder found in Applications, launch IO Registry Explorer that you’ll find in the Hardware folder; also launch the Console utility from Utilities as well.

In the IO Registry Explorer left pane, see if there are any terminated processes. Do this without a plugged in external monitor and then with the monitor plugged in. Take a screen capture. If most of the process termination are seen in IOSurfaceRootUserClient, click on it and then get the PID # (process ID #) and search for it in the Console. It may look complicated but it is not really at all. If you see the process being terminated, crossed out and in red, then it is the video card. See snapshot below. Btw, do repeated snapshots to see if the terminated processes add up in the left pane of the IO Registry Explorer.

This pointed me to look specifically at a special crash in Console, pointed at the GPU:

"Crashed Thread: 2 com.apple.coreanimation.render-server

Exception Type: EXC_CRASH (SIGKILL)

Exception Codes: 0x0000000000000000, 0x0000000000000000

Exception Note: EXC_CORPSE_NOTIFY

Termination Reason: WATCHDOG, [0x1] monitoring timed out for service

Termination Details: WATCHDOG, checkin with service: com.apple.WindowServer returned not alive with context:

unresponsive work processor(s): WindowServer main thread

90 seconds since last successful checkin, 53 total successful checkins since load, 49 seconds since last crashed by watchdogd, (1 induced crashes)

Application Specific Information:

StartTime:2019-10-12 21:00:07

GPU:IG&AMD

MetalDevice for accelerator(0x4803): 0x7f8fced0bfc8 (MTLDevice: 0x7f8f90098000)

MetalDevice for accelerator(0x4c27): 0x7f8fced10888 (MTLDevice: 0x7f8fa00b0000)

IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/PEG0@1/IOPP/EGP0@0/IOPP/EGP1@0/IOPP/GFX0@0/ATY,Xingu@1/AMDFramebufferVega10

IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/PEG0@1/IOPP/EGP0@0/IOPP/EGP1@0/IOPP/GFX0@0/ATY,Xingu@0/AMDFramebufferVega10

"

Also, I sent my Mac already to Apple for repair.

I got solution for my MacBook pro:

10.15.1 (19B2106)

2.4 GHz 8-Core Intel Core i9

32 GB 2667 MHz DDR4

AMD Radeon Pro 5500M 8 GB

Intel UHD Graphics 630 1536 MB

According to the introduction gaven by Apple support that use Option-⌘-R to update system to newest version.

https://support.apple.com/HT204904

My system have not crashed around 1 day (include 2 times wake up):

% uptime
20:21  up 23:47, 2 users, load averages: 4.16 4.62 4.08

I got my iMac back from Apple this weekend, with a replaced logic board. I was very skeptical that it was going to fix the Kernel Panic issue when going to sleep since 1) the problem only began with Catalina, and 2) the problem disappeared when I rolled backed to Mojave. But surprisingly, the problem has gone away with the new logic board!

I was told engineering's explanation was that Catalina might be using different features of the GPU, thus the hardware problem is only evident when running Catalina. Again, I remain skeptical. I did look for any obvious differences in firmware on the new logic board to better explain why the problem has been resolved but couldn't find any.

Hopefully it doesn't turn out that this is a hardware problems for others in this thread as well, as it's obviously an expensive repair and I only went down this path since I had AppleCare.

Something that seems to have worked for me (fingers crossed) is not using any Sleep mode, including manually when leaving the computer for a short while.

I have not had a Kernel Panic in over six days now; before, I use to have one about every 36 hours.

Under Energy Saver settings, I have only one box checked, "Prevent computer from sleeping automatically when the display is off", and I have set "Turn display off after 15 minutes".

Again, I never put the computer to sleep manually, and I also turn off the computer every night, restarting it in the morning.

This is with a mid-2014 iMac that is using an external SSD as the startup drive.

I have two iMacs and one MacBook Pro that are all operating on Catalina. One of the iMacs was constantly (at least 5 times a day) crashing after the Catalina upgrade. The other iMac and MacBook Pro had absolutely NO problem with Catalina.

After switching out the thunderbolt to thunderbolt cord with my Lacie Drive, the problem iMac no longer crashes. Turns out that the cord that came with the hard drive was the culprit and after swapping it out with an Apple cord, the iMac works fine.

How odd.