Kernel task eats terabyte a day... Anybody else?

[inc0gnito]

Hi guys,

Another interesting M1 misbehaviour example...

I have noticed that my kernel_task process wrote over 9 terabytes of data within a week... I have a feeling that's a bit much?! Computer spent most of the time sleeping and when on, it was only used for browsing.

Yes - I do use on average 10+ tabs if anyone wonders... It's an MBA M1 8GB machine. Also computer has been on only for a week.

I did a reboot yesterday evening and since kernel_task already wrote over 1.7 tb of data - NVRAM reset done.

Any thoughts how to address that?

(P.s I did post this in different part of the forum but haven't received much response - admin pls feel free to delete if I am breaching rules. Thanks!)

 

[alien3dx]

MacBook m1 base 8 GB .. most of hardcore using iMac.

iMac also kernel 13 gb... (a lot usage)

 

[CheesePuff]

That seems AWFULLY high... but not sure what would be causing it. For comparison after 3 days on mine kernel_task process has written under 10 GB

 

[SquealingCustard]

13gb for mine.

 

[Leon1das]

How come I have 0? Do I read this properly? M1 MBP 8Gb.

 

[alien3dx]

View attachment 1712013
How come I have 0? Do I read this properly? M1 MBP 8Gb.

wait a 2 second it will appear

 

[inc0gnito]

View attachment 1712013
How come I have 0? Do I read this properly? M1 MBP 8Gb.

You have to go to disk tab

 

[Leon1das]

OK, here is the update - ~850Mb

Edit. had to remove photo (privacy thing)... here is it again...

P.S. Just to add:
- I reinstalled my new M1 MBP before I started to use it (Erase Mac - Reinstall via Recovery with Internet)
- I migrated my apps/documents/settings from my MBA

 

[jdb8167]

I would reinstall from scratch and then manually migrate. That is not normal.

 

[pmiles]

kernel_task is the systems way of trying to cool itself.

If kernel_task is using a large percentage of your Mac CPU - Apple Support

One of the functions of the kernel task process is to help manage the temperature of your CPU.

support.apple.com

 

[Runs For Fun]

What is your memory pressure? I have a feeling this may have to do with swapping.

 

[inc0gnito]

kernel_task is the systems way of trying to cool itself.

If kernel_task is using a large percentage of your Mac CPU - Apple Support

One of the functions of the kernel task process is to help manage the temperature of your CPU.

support.apple.com

Yeah I have read about it - the thing is that my cpu usage seems fine. Kernel is usually in lower 10%.

Laptop doesn't really get warm either.

 

[inc0gnito]

What is your memory pressure? I have a feeling this may have to do with swapping.

I am not going to lie - I do use multiple apps, but kernel runs such a big amounts of data even when only one app is on.

So far I have removed avast just to see if there is any difference. Also experimented with mail apps - no difference.

I thought it could have been faulty temperature system, but diagnostic showed nothing wrong.

 

[Runs For Fun]

I am not going to lie - I do use multiple apps, but kernel runs such a big amounts of data even when only one app is on.

So far I have removed avast just to see if there is any difference. Also experimented with mail apps - no difference.

I thought it could have been faulty temperature system, but diagnostic showed nothing wrong.

9.6GB of swap used. That’s probably a big part of the problem.

 

[mlykke]

This is because the computer is swapping a lot. And this is the exact reason I keep telling people to get the 16 GB model.
Out of 8 GB of ram, aproximately 6-6.5 GB is available - The rest goes to the GPU cores. With Mac Os easily using 3-4 GB after it's been running for a few hours, that basically leaves you with 2 GB for everything else, which is absolutely nothing. This then forces the computer to swap like crazy.
Even if your memory pressure is green, that is NOT an indication that everything is good memory wise. It will usually be green even when the computer is swapping like mad. My computer currently is using 30 gb of swap and memory pressure is green. But the computer is substantially slower compared to when it's barely using any swap at all. The memory pressure metric is useless for everything but showing when it spikes high temporaily.

 

[Del Martes]

This is because the computer is swapping a lot. And this is the exact reason I keep telling people to get the 16 GB model.
Out of 8 GB of ram, aproximately 6-6.5 GB is available - The rest goes to the GPU cores. With Mac Os easily using 3-4 GB after it's been running for a few hours, that basically leaves you with 2 GB for everything else, which is absolutely nothing. This then forces the computer to swap like crazy.
Even if your memory pressure is green, that is NOT an indication that everything is good memory wise. It will usually be green even when the computer is swapping like mad. My computer currently is using 30 gb of swap and memory pressure is green. But the computer is substantially slower compared to when it's barely using any swap at all. The memory pressure metric is useless for everything but showing when it spikes high temporarily.

The 2GB should be enough, if you just web browse, email and read a few PDF books, right?

(The PDF books usually range between 20 to 100 MBS.)

I'm not an IT pro. Just want to put the question there.

 

[alien3dx]

I am not going to lie - I do use multiple apps, but kernel runs such a big amounts of data even when only one app is on.

So far I have removed avast just to see if there is any difference. Also experimented with mail apps - no difference.

I thought it could have been faulty temperature system, but diagnostic showed nothing wrong.

app name? hope not lightroom

 

[Quackers]

You've dumped Avast I see. Have you got Norton running? I'd try dumping that, if you have.
I also see you've got Microsoft Edge, Opera and Safari running.
Maybe you could narrow down a cause if you just tried using Safari for the moment, making sure that Edge and Opera are running nothing after you stop using them.

 

[rui no onna]

The 2GB should be enough, if you just web browse, email and read a few PDF books, right?

(The PDF books usually range between 20 to 100 MBS.)

I'm not an IT pro. Just want to put the question there.

A single Amazon tab in Safari uses around 400MB on my MBA. If you keep a lot of tabs open, then that's a lot of swapping.

@inc0gnito Can you try running https://binaryfruit.com/drivedx and post a screenshot of Health Indicators?

The TBW specification for retail SSDs are for warranty purposes and is more of worst case with write amplification.

If we look at raw NAND writes at 3,000 P/E cycles (typical for 3D TLC NAND), that's 256GB: 768TBW; 512GB: 1.5PBW; 1TB: 3PBW; 2TB: 6PBW. I'm interested in estimating the TBW or P/E cycle rating for the Apple SSDs.

Here's another thread discussing the seemingly unusually high writes.

Smartmontool Reporting abnormally high SSD write activities?

Hi all, I have been using the lowest end Mac mini (8GB RAM, 256GB SSD) for two weeks now, and I am pretty happy with it. My workflow doesn't seem to stress the CPU that much, and memory pressure stays in the green zone 95% of the time. When I start coding and running emulators in Xcode, it...

forums.macrumors.com

 

[Runs For Fun]

The 2GB should be enough, if you just web browse, email and read a few PDF books, right?

(The PDF books usually range between 20 to 100 MBS.)

I'm not an IT pro. Just want to put the question there.

No that’s probably not enough. Web browsers these days use massive amounts of resources.

 

[Runs For Fun]

This is because the computer is swapping a lot. And this is the exact reason I keep telling people to get the 16 GB model.
Out of 8 GB of ram, aproximately 6-6.5 GB is available - The rest goes to the GPU cores. With Mac Os easily using 3-4 GB after it's been running for a few hours, that basically leaves you with 2 GB for everything else, which is absolutely nothing. This then forces the computer to swap like crazy.
Even if your memory pressure is green, that is NOT an indication that everything is good memory wise. It will usually be green even when the computer is swapping like mad. My computer currently is using 30 gb of swap and memory pressure is green. But the computer is substantially slower compared to when it's barely using any swap at all. The memory pressure metric is useless for everything but showing when it spikes high temporaily.

But 8gB On ThE M1 is MAgicAl!

 

[Zazoh]

Ya, I don't like blanket comments about needing more memory. I'm a programer. Had zoom calls half the day and VM Ware Horizon connected to Windows Machines at work, Safari, Messages and a few other apps running.

Here is how much swap I was using ... ZERO



I know many of you have 97 tabs open, three streams of YouTube running simultaneously while converting your 10K song iTunes library to a higher format. But for the regular Joe who uses a laptop. 8 is plenty.

 

[SegNerd]

As far as I know, there are many different possible causes for kernel_task to start using a ton of resources. All it really means is that your system’s core resources are being used a lot - which can really mean almost anything.

Unfortunately, you will probably just have to use trial and error to figure out the cause.

 

[w0lf]

First thing I would try is create a new user account and use it for a few hours without any third party apps installed.

If you're not seeing the insane kernel task usage then you can narrow it down to being either an issue with something about the user account being corrupt or a 3rd party app.

Continuing from there start installing and using some third party apps while carefully monitoring your kernel task usage and within a day or so you should know where the issue lies.

 

[Wizec]

Hi guys,

Another interesting M1 misbehaviour example...

I have noticed that my kernel_task process wrote over 9 terabytes of data within a week... I have a feeling that's a bit much?! Computer spent most of the time sleeping and when on, it was only used for browsing.

Yes - I do use on average 10+ tabs if anyone wonders... It's an MBA M1 8GB machine. Also computer has been on only for a week.

I did a reboot yesterday evening and since kernel_task already wrote over 1.7 tb of data - NVRAM reset done.

Any thoughts how to address that?

(P.s I did post this in different part of the forum but haven't received much response - admin pls feel free to delete if I am breaching rules. Thanks!)

Here’s an interesting thread about how Spotlight can cause something like this:

kernel_task writes terabytes of data - Apple Community

discussions.apple.com