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Seanm87

macrumors 68020
Original poster
Oct 10, 2014
2,252
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Base MacBook Pro 14 inch here.

Since upgrading to 12.1 my MacBook gets hot doing very menial tasks such as browsing the web and watching YouTube. Checking activity monitor shows that WindowServer is using over 100% of computing power. I restart the laptop which fix things temporarily before this issue returns (again not doing anything intensive).

Any ideas how to fix this?
 
Hi!
Firstly, let your Mac handle all background processes. I'm sure that after a few hours it will back to normal.
But make sure that Mac is on power cord + Prevent your Mac from automatically sleeping when the display is off is enabled (System Preferences -> Battery -> Power Adapter)
 
Base MacBook Pro 14 inch here.

Since upgrading to 12.1 my MacBook gets hot doing very menial tasks such as browsing the web and watching YouTube. Checking activity monitor shows that WindowServer is using over 100% of computing power. I restart the laptop which fix things temporarily before this issue returns (again not doing anything intensive).

Any ideas how to fix this?
What browser? Safari chrome or?
 
MacBook Pro 14 just updated yesterday and noticed this too! Ugh! Why do they have to release buggy updates
and 100% just means 1 of the cores (or spread across basically) is maxed out.
 

Attachments

  • Screen Shot 2021-12-16 at 5.39.03 am.png
    Screen Shot 2021-12-16 at 5.39.03 am.png
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It's related to the memory leakage of Window Server. If you see Window Server maxing out a CPU core, also check its RAM usage and you will see it has started leaking tons of memory. Just had it happen yesterday on my M1 Max. Fans on, 27W power draw, one CPU core maxed out by Window Server and Window Server memory usage up at 8GB.
 
It's related to the memory leakage of Window Server. If you see Window Server maxing out a CPU core, also check its RAM usage and you will see it has started leaking tons of memory. Just had it happen yesterday on my M1 Max. Fans on, 27W power draw, one CPU core maxed out by Window Server and Window Server memory usage up at 8GB.
Jeez! I have 32GB on my M1 Pro and so far it's only been taking up around 2GB. I'm uploading a bug report to Apple right now with all the needed reports. I put it under a Fans and Heat problem. They better patch this quick
 
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Wait several days, ...
Depending on your settings Macos is "Optimising your system" after the update.
Reindexing everything you haven't asked him to (Check your Spotlight settings, If they haven't disappeared)
Doing bunch of stuff you didn't asked him to do and that you don"t wan't to happen (Icloudd, studentd, gamesd, stockd, mtlcompilerservice, Xcode, ...)
The more HD space and the more applications you have, the longer it takes.

After some time he does not find anything else to bother you with and the temp comes back to normal.
Some Apple users are happy that Apple decides, what's best for you!

In my personal case I don't judge the update before 1 week of usage, since Big Sur.
I had 1 Apple hardware and it will be the last, because the software is 10 years old and getting older.
 
The Window Server load has nothing to do with system optimization. It's an old and known bug that is randomly bugging even installs that have been up and running for quite a while. Killing Window Server or rebooting the OS fixes it until it eventually starts misbehaving again.
 
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The Window Server load has nothing to do with system optimization. It's an old and known bug that is randomly bugging even installs that have been up and running for quite a while. Killing Window Server or rebooting the OS fixes it until it eventually starts misbehaving again.
I agree on the load over time, not the temp, which is the question asked by OP!
 
Well, read his question again.
Checking activity monitor shows that WindowServer is using over 100% of computing power. I restart the laptop which fix things temporarily before this issue returns (again not doing anything intensive)

Edit: FYI here is another user on Reddit complaining about exactly the same thing:
And there even is a recent topic about this on Macrumors covering the mem leak issues of Monterey in general which also contains some reports about the Window Server issues. https://forums.macrumors.com/threads/memory-leaks-in-monterey.2321357/
 
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Well, read his question again.


Edit: FYI here is another user on Reddit complaining about exactly the same thing:
And there even is a recent topic about this on Macrumors covering the mem leak issues of Monterey in general which also contains some reports about the Window Server issues. https://forums.macrumors.com/threads/memory-leaks-in-monterey.2321357/
Question of the OP is:

Macbook gets hot since upgrading to 12.1?​

Make your own thread!

Update is 2 days old, the reason is the upgrade not another underlying problem!
 
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And by the way:
Checking activity monitor shows that WindowServer is using over 100% of computing power.
Except on an Apple devices, that does not exit, as well as 2500 % of RAM usage.
They went too far on advertising this time :)

Even the people with problems believe the fake M1 performance reports!
 
Oh, so you are one of those people that only read titles (which in this case isn't even a question!), what's written below doesn't matter. That disqualifies you from any discussion.
 
Oh, so you are one of those people that only read titles (which in this case isn't even a question!), what's written below doesn't matter. That disqualifies you from any discussion.
Hello Trump!
Just answering a question not talking about myself ;)
 
And Yes, On Forums we answer to questions, maybe that is something difficult to understand.
 
FWIW, I captured a spindump while WindowServer was going berserk on my 14" M1 Max; same symptoms (constant ~100% CPU utilization — note that 100% = one core, not 100% of the entire CPU!), but also:

Screen Shot 2021-12-16 at 6.56.57 PM.png


That's a lot of memory. More to the point, though, I have a possible suspect:

Screen Shot 2021-12-16 at 7.58.50 PM.png


That is a WindowServer stats collection thread that consumed ~10 seconds of CPU time during a 10-second sample — which corresponds to 100% of one core for 10 seconds. Hmmm.

Here's the same thread after rebooting the system to get WindowServer running normally again:

Screen Shot 2021-12-16 at 7.59.37 PM.png


That's a whopping 7 milliseconds out of the same 10-second sample time — in other words, effectively nothing.

I think what's happening, at least in this particular case, is that a background stats collection process is getting screwed up somehow and ends up running in an infinite loop, consuming excessive CPU time and leaking a boatload of memory in the process.

Anyone else want to try to reproduce on their own machine and see if you get the same result? Here's how:
  1. Start Activity Monitor (it's in /Applications/Utilities)
  2. Select the CPU tab
  3. From the View menu, select All Processes
  4. Sort the list by % CPU, descending (highest utilization on top)
  5. Find WindowServer in the list and select it
  6. From the (...) menu at the top of the window, choose Spindump and enter your password if prompted
This will collect a 10-second sample of all running processes, with the selected process at the top of the list below the report header. Search for "com.apple.skylight.stats", and check the value reported for cpu time (as highlighted in the screenshots above). A value close to 10s would indicate that the same thread is misbehaving as my example here.
 
FWIW, I captured a spindump while WindowServer was going berserk on my 14" M1 Max; same symptoms (constant ~100% CPU utilization — note that 100% = one core, not 100% of the entire CPU!), but also:

View attachment 1929726

That's a lot of memory. More to the point, though, I have a possible suspect:

View attachment 1929727

That is a WindowServer stats collection thread that consumed ~10 seconds of CPU time during a 10-second sample — which corresponds to 100% of one core for 10 seconds. Hmmm.

Here's the same thread after rebooting the system to get WindowServer running normally again:

View attachment 1929728

That's a whopping 7 milliseconds out of the same 10-second sample time — in other words, effectively nothing.

I think what's happening, at least in this particular case, is that a background stats collection process is getting screwed up somehow and ends up running in an infinite loop, consuming excessive CPU time and leaking a boatload of memory in the process.

Anyone else want to try to reproduce on their own machine and see if you get the same result? Here's how:
  1. Start Activity Monitor (it's in /Applications/Utilities)
  2. Select the CPU tab
  3. From the View menu, select All Processes
  4. Sort the list by % CPU, descending (highest utilization on top)
  5. Find WindowServer in the list and select it
  6. From the (...) menu at the top of the window, choose Spindump and enter your password if prompted
This will collect a 10-second sample of all running processes, with the selected process at the top of the list below the report header. Search for "com.apple.skylight.stats", and check the value reported for cpu time (as highlighted in the screenshots above). A value close to 10s would indicate that the same thread is misbehaving as my example here.
nice investigating. i did take a spindump and full sysdiagnose and sent the reports to apple bug report as we are meant to.
i had a quick look through the spindump but wasn’t 100% what i was looking for. there were a lot of processes running through the windowserver so i assumed that proved there was something bad inside.
i got the problem to stop by turning off auto sleep when display is off while connected to power overnight. cpu went down by morning and i restarted and the excess ram was gone. hasn’t happened so far since
 
nice investigating. i did take a spindump and full sysdiagnose and sent the reports to apple bug report as we are meant to.
i had a quick look through the spindump but wasn’t 100% what i was looking for. there were a lot of processes running through the windowserver so i assumed that proved there was something bad inside.
i got the problem to stop by turning off auto sleep when display is off while connected to power overnight. cpu went down by morning and i restarted and the excess ram was gone. hasn’t happened so far since
In the spindump file, you have a header section that provides an overview for the report, and below that is a (very long) list of processes and thread data (most of which can be safely ignored if you're not the one actually debugging the issue).

What you're looking for is the top line for the thread being used by "com.apple.skylight.stats" (just search for it in the file, it should only be in there once); the "cpu time" value should be near the end of that line, and you're checking for the amount of time reported in seconds.
 
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