Constant Kernel Panics – userspace watchdog timeout: no successful checkins from com.apple.WindowServer

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
I have been receiving these kernel panics multiple times a day (the computer freezes, followed by an eventual crash/restart if I don't do a hard shut down first). It occurs most frequently when waking the computer from sleep. Often I'll go to the bathroom and return to my computer, only to see my screensaver has frozen (at which point I'll be forced to do a hard shut down) or I'll come back and see my login screen (meaning the computer shut itself down). When logging back in, I receive the full kernel panic (attached below).

That said, certain applications seem to cause it while the computer is in use: Skype, Plex, iMovie, and occasionally while watching YouTube/Netflix. During a 45 minute Skype call, I'll get the freezing about 3 times. And as you can see from the embedded video, I can repeatedly produce the kernel panic using iMovie in just 2-3 minutes.


My guess is the issue stems from the Mac's use of the discrete GPU, probably the GPU driver because this issue began with a software (or potentially silent firmware) update and, according to others on the Apple Support Threads, is occurring on dozens of different models, meaning different GPUs. This is further evidenced by the fact that many of the applications I experience the crash while using require the discrete GPU to be used (and some especially tax it), as well as other users experiencing the crash when they plug their Mac into an external monitor, which likely triggers a switch to or more heavily involves the discrete GPU.

Here are steps you can do to reproduce the issue on your Mac running Catalina:
  1. (If you have a laptop) Open System Preferences, then go to Energy Saver, then deselect "Automatic Graphics Switching" at the top. This will make it so that your dedicated GPU is always in use.
  2. Go to this link and download the 4K video: https://www.videezy.com/urban/2820-aerial-footage-of-new-york-city-4k
  3. Open the video in Quicktime.
  4. In the menu bar, click "View" and then "Loop" so the video plays repeatedly.
  5. Play the video and wait.
Using this method I was able to cause my laptop to kernel panic with this error within 30 seconds of playing the video. I repeated the process 6 times just to be sure, and each time my computer kernel paniced with this error within 30 seconds every time.

Let's please figure this out. It's impossible to downgrade a 16-inch MBP to Mojave because it shipped with Catalina, so I'm stuck without any remedy here. I've tried a completely fresh install of Catalina, but that didn't resolve the issue.

Here's the panic:
Code:
panic(cpu 2 caller 0xffffff7f9cb9dad5): userspace watchdog timeout: no successful checkins from com.apple.WindowServer in 120 seconds
service: com.apple.logd, total successful checkins since load (6130 seconds ago): 614, last successful checkin: 0 seconds ago
service: com.apple.WindowServer, total successful checkins since load (6100 seconds ago): 598, last successful checkin: 120 seconds agoBacktrace (CPU 2), Frame : Return Address
0xffffff924115b820 : 0xffffff801c13bb2b
0xffffff924115b870 : 0xffffff801c2734d5
0xffffff924115b8b0 : 0xffffff801c264f4e
0xffffff924115b900 : 0xffffff801c0e2a40
0xffffff924115b920 : 0xffffff801c13b217
0xffffff924115ba20 : 0xffffff801c13b5fb
0xffffff924115ba70 : 0xffffff801c8d2b25
0xffffff924115bae0 : 0xffffff7f9cb9dad5
0xffffff924115baf0 : 0xffffff7f9cb9d7e6
0xffffff924115bb10 : 0xffffff801c86739b
0xffffff924115bb60 : 0xffffff801c870443
0xffffff924115bca0 : 0xffffff801c222d12
0xffffff924115bdb0 : 0xffffff801c1419d8
0xffffff924115be10 : 0xffffff801c118635
0xffffff924115be70 : 0xffffff801c12f0e5
0xffffff924115bf00 : 0xffffff801c24b575
0xffffff924115bfa0 : 0xffffff801c0e3226
      Kernel Extensions in backtrace:
         com.apple.driver.watchdog(1.0)[053A5D15-51D4-3E61-978B-EB435FA4BD0A]@0xffffff7f9cb9c000->0xffffff7f9cba4fffBSD process name corresponding to current thread: watchdogd
Boot args: chunklist-security-epoch=0 -chunklist-no-rev2-devMac OS version:
19D76Kernel version:
Darwin Kernel Version 19.3.0: Thu Jan  9 20:58:23 PST 2020; root:xnu-6153.81.5~1/RELEASE_X86_64
Kernel UUID: A8DDE75C-CD97-3C37-B35D-1070CC50D2CE
Kernel slide:     0x000000001be00000
Kernel text base: 0xffffff801c000000
__HIB  text base: 0xffffff801bf00000
System model name: MacBookPro16,1 (Mac-E1008331FDC96864)
System shutdown begun: NO
 
Last edited:

Nico82

macrumors newbie
Feb 10, 2020
2
0
It suddenly started about a week ago. Every time I leave my 2019 iMac alone for a few minutes (maybe ten or so) it freezes and then restarts. However, it never happens during the time I use it.

There are many threads online about this issue, but no solution yet.
 

José-María Súnico

macrumors newbie
Feb 11, 2020
1
0
Same here. The computer freezes for some unknown underlying issue (kernel panics sometimes refer to a hard disk problem, in others there are references to the gnu, so my guess is that it has to do with the driver of the gnu and/or the SATA driver, so different events fire the underlying issue).
In my case the freezing happens also when I am using the computer.

When I first upgraded to catalina, 10.15.0 I just experienced the waking up issue.

In 10.15.1 there were a few isolated freezes every now and then, but tolerable.

In 10.15.2 it was much more frequent: indeed when it came 10.15.3 I thought this was because of these. Instead, when I upgraded to 10.15.3 it was even worst, freezing/kernel panics a few times per hour (although there were a few times were the system carried a time machine copy at night without failing, so I would not even discard the problem comes from the user interface...)
Also, I checked that the system fails in cascade: Firstly, the application you are using, but you can for a few seconds switch to other apps. when switching, if you try to access the disk, it always fails, but I have been able to, e.g., pop the menu of some apps... in any case, in matter of seconds all apps freeze, and then a few minutes later the hateful kernel panic black screen noting the system will reboot shortly.

As I upgraded from Mojave, I did a clean install of 10.15.3, but no changes and it hangs even just surfing the web with safari.

I have checked at an AAPFS, and they say (I pick the computer next Friday) that everything worked just right testing the computer with a Mojave external disk, and they advise me not to install Catalina for now.

I understand bugs happen, and I love Apple products, but for those of us who trust Apple, we expect prompt communication on these kind of problems, especially when you have uploaded dozens of kernel panic reports, it is just good customer management. A clear communication acknowledging the problem, sharing known issues, some initial advises and providing information on future (coming) updates, would be very welcome.
 

P_Watt

macrumors newbie
Dec 10, 2018
1
0
Even though I updated an older Macbook Pro to Catalina with no problems at all and improved speed, I have advised the rest of my family to stick with Mojave. It isnt clear what benefits are available and the loss of iTunes is too much for them.
One thing is clear From the Apple Discussion forum is that there is no one single cause for these KPs because some have cured the problem but the posted remedies don't help some others.
 

Matthias Schmieder

macrumors newbie
Feb 11, 2020
2
0
As I wrote in the Support Community Thread already I have the same experience but my machine does not restart - only the WindowServer gets killed and restarted. I can provoke it by switching between desktops by swiping left and right even without having my displays plugged in.

I'm on a 2018 MBP 13"

This are the error logs I'm getting:

Code:
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: WindowServer returned not alive with context:
unresponsive dispatch queue(s): com.apple.WindowServer.HIDEvents unresponsive work processor(s): WindowServer main thread
40 seconds since last successful checkin, 58 total successsful checkins since wake (0 induced crashes)

Application Specific Information:
StartTime:2020-02-10 14:57:39
GPU:IG
MetalDevice for accelerator(0x3133): 0x7fbc22e24d68 (MTLDevice: 0x105f95000)
IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/IGPU@2/AppleIntelFramebuffer@0
 

benthewraith

macrumors 68040
May 27, 2006
3,083
80
Miami, FL
Let's please figure this out. It's impossible to downgrade a 16-inch MBP to Mojave because it shipped with Catalina, so I'm stuck without any remedy here. I've tried a completely fresh install of Catalina, but that didn't resolve the issue.

Here's the panic:
Code:
panic(cpu 4 caller 0xffffff7f8539fad5): userspace watchdog timeout: no successful checkins from com.apple.WindowServer in 120 seconds service: com.apple.logd,
total successful checkins since load (250 seconds ago): 26,
last successful checkin: 0 seconds ago service: com.apple.WindowServer,
total successful checkins since load (220 seconds ago): 10, last successful checkin: 120 seconds ago
This issue isn't just happening with discrete graphics, it's also happening with those running intel iGPUs. WoW is currently unplayable, it was fixed by disabling particle effects. It prevents crashes, but doesn't make the game playable when you can't see things on the ground or other spell effects. My guess is a memory leak related to Metal API as people are seeing their video RAM hit hard. The only fix for WoW players is to downgrade to High Sierra, which is a pain in the ass.


It's a huge problem seeing as there's close to 2000 responses in the US forums and 1000 responses in the EU forums.
 

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
This issue isn't just happening with discrete graphics, it's also happening with those running intel iGPUs. WoW is currently unplayable, it was fixed by disabling particle effects. It prevents crashes, but doesn't make the game playable when you can't see things on the ground or other spell effects. My guess is a memory leak related to Metal API as people are seeing their video RAM hit hard. The only fix for WoW players is to downgrade to High Sierra, which is a pain in the ass.


It's a huge problem seeing as there's close to 2000 responses in the US forums and 1000 responses in the EU forums.
Oh wow, very good to know. Sounds like this goes beyond just a single graphics driver. Perhaps this is the way the OS interfaces with GPUs or something? It still seems like this is related to the GPU in some way.

Have you been able to produce the issue on your machine outside of playing games?

Also, how are you guys monitoring your VRAM usage? I would like to monitor that to see if it corresponds with the shutdowns.
 

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
Same here. The computer freezes for some unknown underlying issue (kernel panics sometimes refer to a hard disk problem, in others there are references to the gnu, so my guess is that it has to do with the driver of the gnu and/or the SATA driver
By "GNU" do you mean GPU?
- - Post merged: - -

As I wrote in the Support Community Thread already I have the same experience but my machine does not restart - only the WindowServer gets killed and restarted. I can provoke it by switching between desktops by swiping left and right even without having my displays plugged in.

I'm on a 2018 MBP 13"

This are the error logs I'm getting:

Code:
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: WindowServer returned not alive with context:
unresponsive dispatch queue(s): com.apple.WindowServer.HIDEvents unresponsive work processor(s): WindowServer main thread
40 seconds since last successful checkin, 58 total successsful checkins since wake (0 induced crashes)

Application Specific Information:
StartTime:2020-02-10 14:57:39
GPU:IG
MetalDevice for accelerator(0x3133): 0x7fbc22e24d68 (MTLDevice: 0x105f95000)
IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/IGPU@2/AppleIntelFramebuffer@0
Did this start in Catalina? Or were you having these issues before upgrading?
 

fruit of Zappa's loins

macrumors newbie
Dec 6, 2019
3
1
I have Catastra**** 10.15.3 installed and it crashes randomly. In the 1990s I ran a Windows machine for literally 2 years 24 hours a day searching for a Mersenne prime and thanks to some fantastic assembly code by the inimitable George Woltman I never, ever , ever had a crash with Windows of that era. George designed the application to run 100% CPU all the time ie the large number calculations would soak up any excess CPU time. Scroll forward a generation and Apple cannot produce a stable operating system. I prostrate myself before their technical genius. Screen Shot 2020-02-13 at 7.35.27 pm.png
 
Last edited:

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
It started right after upgrading to Catalina. My colleague who sits right next to me with the same MBP never experienced these issues...
That is very frustrating. I just figured out how to reproduce the issue on, I think, any Mac running Catalina. Can you and your colleague follow these steps and let me know if neither, one, or both of your machines crash?

Here are steps you can do to reproduce the issue on your Mac running Catalina in just 3 minutes:
  1. (If you have a laptop) Open System Preferences, then go to Energy Saver, then deselect "Automatic Graphics Switching" at the top. This will make it so that your dedicated GPU is always in use.
  2. Go to this link and download the 4K video: https://www.videezy.com/urban/2820-aerial-footage-of-new-york-city-4k
  3. Open the video in Quicktime.
  4. In the menu bar, click "View" and then "Loop" so the video plays repeatedly.
  5. Play the video and wait.
 
Last edited:

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
Even though I updated an older Macbook Pro to Catalina with no problems at all and improved speed, I have advised the rest of my family to stick with Mojave. It isnt clear what benefits are available and the loss of iTunes is too much for them.
One thing is clear From the Apple Discussion forum is that there is no one single cause for these KPs because some have cured the problem but the posted remedies don't help some others.
I got the following message from the Apple Support Forums, saying that they're about to delete my account if I keep posting something that is very reasonable: the way I've been able to reproduce this issue (which is an essential part of discovering a fix for the bug and testing when the bug has been fixed).

Can you contact the moderators for me and have them approve this message?

Hi Joe (Monstermac77),

In the past, you submitted a number of posts to the Apple Support Communities site that were inappropriate. At that time, we contacted you to let you know about our submission guidelines and examples of appropriate and inappropriate postings.

This message is your last warning. If you send any more inappropriate posts, we may suspend your ability to use the Apple Communities site. We may also block the Internet Provider address(es) you post from and notify your Internet Service Provider.

If you create new Apple ID(s) and post inappropriate content, we’ll disable the ID(s) without warning.

You can read our submission guidelines here: Apple Support Communities Use Agreement

We’ve included a copy of your most recent post below.

Thanks,

Apple Support Communities Staff

Using this method I was able to cause this issue with the watchdog error within 30 seconds of playing the video. I repeated the process 6 times just to be sure, and each time I got this error within 30 seconds.
  1. (If you have a laptop) Open System Preferences, then go to Energy Saver, then deselect "Automatic Graphics Switching" at the top. This will make it so that your dedicated GPU is always in use.
  2. Go to this link and download the 4K video: https://www.videezy.com/urban/2820-aerial-footage-of-new-york-city-4k
  3. Open the video in Quicktime.
  4. In the menu bar, click "View" and then "Loop" so the video plays repeatedly.
  5. Play the video and wait.
 

fruit of Zappa's loins

macrumors newbie
Dec 6, 2019
3
1
I got the following message from the Apple Support Forums, saying that they're about to delete my account if I keep posting something that is very reasonable: the way I've been able to reproduce this issue (which is an essential part of discovering a fix for the bug and testing when the bug has been fixed).

Can you contact the moderators for me and have them approve this message?
This is outrageous and is why I will never buy Apple again.
 

bobbydd21

macrumors regular
Nov 26, 2012
232
24
Also randomly getting this panic. I am using a TS3+ dock with 2 4k monitors. I am thinking this has something to do with it in my case but it is EXTREMELY annoying.
 

monstermac77

macrumors regular
Original poster
Nov 21, 2007
160
28
Also randomly getting this panic. I am using a TS3+ dock with 2 4k monitors. I am thinking this has something to do with it in my case but it is EXTREMELY annoying.
Can you try the instructions I provided above to see if you can reproduce it without using your doc and monitors? All you have to do is download and play that 4k video for 30-60 seconds.
 

Joshua Wood

macrumors newbie
Feb 18, 2020
1
0
Happening here as well.

panic(cpu 2 caller 0xffffff7f98d9da8d): watchdog timeout: no checkins from watchdogd in 95 seconds (83 total checkins since monitoring last enabled)
Backtrace (CPU 2), Frame : Return Address
0xffffff81e6b8bc40 : 0xffffff801833bb2b
0xffffff81e6b8bc90 : 0xffffff80184734d5
0xffffff81e6b8bcd0 : 0xffffff8018464f4e
0xffffff81e6b8bd20 : 0xffffff80182e2a40
0xffffff81e6b8bd40 : 0xffffff801833b217
0xffffff81e6b8be40 : 0xffffff801833b5fb
0xffffff81e6b8be90 : 0xffffff8018ad2b25
0xffffff81e6b8bf00 : 0xffffff7f98d9da8d
0xffffff81e6b8bf10 : 0xffffff7f98d9d467
0xffffff81e6b8bf50 : 0xffffff7f98db2e76
0xffffff81e6b8bfa0 : 0xffffff80182e213e
Kernel Extensions in backtrace:
com.apple.driver.watchdog(1.0)[053A5D15-51D4-3E61-978B-EB435FA4BD0A]@0xffffff7f98d9c000->0xffffff7f98da4fff
com.apple.driver.AppleSMC(3.1.9)[8D698096-1F90-3679-8151-22A7665ED287]@0xffffff7f98da5000->0xffffff7f98dc3fff
dependency: com.apple.driver.watchdog(1)[053A5D15-51D4-3E61-978B-EB435FA4BD0A]@0xffffff7f98d9c000
dependency: com.apple.iokit.IOACPIFamily(1.4)[3D78401B-5D2D-33BC-9E41-DD2164EA874D]@0xffffff7f98d07000
dependency: com.apple.iokit.IOPCIFamily(2.9)[ADD485B5-3EF8-37C4-B3C5-F86326E497A4]@0xffffff7f98d10000

BSD process name corresponding to current thread: kernel_task
Boot args: chunklist-security-epoch=0 -chunklist-no-rev2-dev

Mac OS version:
19D76

Kernel version:
Darwin Kernel Version 19.3.0: Thu Jan 9 20:58:23 PST 2020; root:xnu-6153.81.5~1/RELEASE_X86_64
Kernel UUID: A8DDE75C-CD97-3C37-B35D-1070CC50D2CE
- - Post merged: - -