Questions tagged [kernel]

The core part of an operating system, responsible for managing resource allocation.

Filter by
Sorted by
Tagged with
3
votes
1answer
774 views

kernel_task writes huge amounts of data to disk (> 1TB) - how to diagnose?

My MacBook (2016 with TouchBar) running macOS 10.13 has a 512GB SSD. Looking at the activity monitor after a couple of weeks of uptime (most of it spent in standby), kernel_task shows 1.43TB (!) of ...
-1
votes
0answers
18 views

macos laptop WakeUp with mouse on USB programmatically [closed]

MacOs, How with a laptop, use the mouse or the keyboard (connected in USB) To WakeUp? On a laptop the WakeUp with MacOs is always achieved by pressing the PowerButton key, the USB ports are made ...
1
vote
4answers
44 views

kernel_task, high CPU and fans going crazy, no applications open, no launch agents/daemons

i've tried to debug this for a couple days straight now and can't find out what's causing the kernel_task to go so unruly. i've removed nearly all my third party kexts, done so many etrepro's, and i'...
0
votes
4answers
33 views

Fans blaring again after a brief hardware fix

My 2017 MacBook Air began having a problem with a high kernel task and high CPU with fans blaring. I did a hardware test and it said there may be an issue with the SMC PFM006, there may be an issue ...
0
votes
0answers
31 views

What are the limitations of Trusted Platform Modules?

Apple introduced DMCA measures (like DSMOS and CPUID Validation) instead of attempting to utilize a Trusted Platform Module (which was physically present on hardware but did not have drivers on Mac OS ...
1
vote
0answers
21 views

2017 MBP has started to degrade in performance - dreaded kernel_task

All - My normally stable mbp 2017 has started slowing down with kernel_thread dominating the CPU in recent weeks. This condition persists across reboots. My primary concern is that the machine is ...
1
vote
0answers
143 views

Undefined Kernel Panic on macOS 10.15.5

I encountered an undefined kernel panic on MacOs Catalina 10.5.5. When panic occurs, the screen goes black suddenly and tihs page appeared: After, Mac restarts itself. I got the panic logs: Log 1: ...
0
votes
1answer
182 views

Kernel Task is using 1000% of The CPU on macOS Catalina [duplicate]

My MacBook Pro running on macOS Catalina is really slow and the kernel task is using 1000% of the CPU !! I tried all the solutions suggested in MUF How to Fix Your Mac’s “kernel_task” High CPU Usage ...
1
vote
1answer
57 views

Where are the memory and kernel logs stored in macOS Catalina?

I want to learn how to debug kernel crashes and am not at all familiar with macOS logging. Specifically the logs files that might reveal a system crash for example due to kernel panics. Does Apple ...
0
votes
1answer
31 views

What is kernel_task reading and writing?

On my machine, kernel_task has a very large number of reads and writes compared to my usage. I spend almost all my time online on google chrome. Over the past month, Activity Monitor shows ...
0
votes
0answers
9 views

How can i manually trigger kernel Null pointer dereference error? [migrated]

I am working on an application for which I need to trigger a kernel null pointer de-reference error and check that in logs. I'm not familiar as to how to do that.
0
votes
0answers
52 views

How to differenciate Legitime Kext in Catalina?

Since I have updated to MacOS Catalina 10.15.5 I was notified about the Kext 3rd-party deprecation (Even notifying me I have 2 3rd-Party Kext loading by default at the start-up of the Mac). Since this,...
0
votes
1answer
66 views

iMac restarted 4 times in 24 hours because of a problem

I have a 2017 iMac, 27", with a Fusion HD and it has restarted 4 times over the past 24 hours. I saved the last report. Can anyone discern even a hint as to what is causing it looking at this report?...
2
votes
1answer
325 views

FTDI USB to serial module doesn't work in Catalina [closed]

I can see FTDI module in system report But in arduino it doesn't show up I read that iOS comes with USBSerial.kext which can handle this but I don't see it working for me. I have tried installing ...
0
votes
0answers
95 views

Apple Diagnostic Result PFM006 and Kernel_Task taking upto 300 % of CPU and Depleted Battery

My Macbook Air (2018) Retina battery has depleted within 130 cycles. I was running Windows via Bootcamp in heavy load, letting it discharge fully and charge repeatedly. If I unplug from power source ...
1
vote
1answer
83 views

How to change kernel security level?

My Mac had a kernel security level of 0. Then, I changed the kernel security level to 1. Here's how I changed it to 1: sysctl kern.securelevel=1 I'd like to change it back to 0 becuase my hosts file ...
2
votes
0answers
1k views

kernel_task high CPU consumption and slow Mac

It's not a new problem, I'm facing it for sometime now. My MacBook runs fine all the time but this kernel_task issue occurs whenever it awakes from sleep. No issues with DisplaySleep. I can't put the ...
7
votes
5answers
14k views

macOS Sierra, kernel_task running taking more than 400% of CPU

After upgrading my MacBookPro to macOS Sierra, CPU is running very fast. When I tried to debug the issue, here is what I have found. Solutions that I have already tried. Reset SMC Reset PRAM Tried ...
0
votes
1answer
31 views

Does the bootcamp with Windows 10 use the same kernel that the MacOS uses on a Macbook Pro?

I am just wondering how the boot camp on the macbook pro works? Does it use the same exact kernel as the one that the MacOS uses? Or does bootcamp switch over to a kernel for the windows 10?
322
votes
7answers
251k views

How to find cause of high kernel_task cpu usage?

Occasionally my machine will have a kernel_task instance max out the CPU: This can last from minutes to sometimes hours. The machine is effectively unusable in this state. Restarting doesn't help; a ...
0
votes
0answers
40 views

What side to charge MacBook Pro 2018 with high kernel_cpu task usage?

This is in reference to the answer posted at How to find cause of high kernel_task cpu usage? which suggests that you should move your charging to the right side thunderbolt. However, based on the ...
0
votes
1answer
56 views

kernel_task on Macbook hogging CPU even after OS upgrades/downgrades; possible Flash malware?

On a Macbook Air (13-inch, Early 2015) my girlfriend got one of those "upgrade Flash" pop-ups and hit (Continue/Okay/etc?). This may or may not have anything to do with the current problem but ever ...
8
votes
2answers
12k views

File location of kernel extensions?

Is there an easy way to make the mapping from kernel extension to the file it came from? I can get the list of currently loaded kernel extension via kextstat. This gives me the bundle names, like com....
9
votes
2answers
248 views

Does macOS still use Yarrow as it's cryptographically secure pseudorandom number generator?

I'm trying to understand if the XNU underpinnings of macOS (BSD) still use the Yarrow cryptographically secure pseudorandom number generator? I have looked through the source and it seems as if they ...
0
votes
1answer
31 views

Can I change my kernel security level?

When I run sysctl kern.securelevel on my Mac, it gives me a value of 0. I'd like to increase the kernel security level on my computer. I want it to give me a 1. Can I do that?
0
votes
0answers
83 views

Interpreting a recurring Kernel Panic

I am getting so many kernel panics and I can't find what is causing them – there is nothing to reproduce it, it just happens at seemingly random times. Is anyone able to decipher what this means to ...
2
votes
1answer
2k views

Is there a way to see what kernel task is doing?

I found a question (and answers) about What exactly does kernel_task do?. What I want to know is how I can inspect what kernel_task is doing at any given moment in time? Does it get logged so that I ...
0
votes
1answer
27 views

kernel_task takes a lot of memory

My kernel_task takes 71.2G VIRT and 2386M RES (in htop screen). I'd like to understand what takes so much resource. But I don't understand what is wrong based on the output of sudo zprint -t https://...
1
vote
1answer
51 views

debug kernel_task large memory usage

htop shows kernel_task used 25% of the memory on 8GB memory Macbook Air. But the sum of the size column of kextstat is only 31830608. I think this number is in bytes? Why is there a difference in ...
1
vote
1answer
152 views

colorsync.display high cpu

PID 217, colorsync.display is pegged at 119% CPU, any ideas what this is or what might be causing it? EDIT: It is happening again EDIT EDIT (12/27/2019): Happening again with no cause known yet... ...
0
votes
1answer
921 views

BUG in system.log, DEPRECATED USE in libdispatch client. Strange things in system report [duplicate]

MacBook Pro 13" Mojave 10.14.6 2.3 Ghz 8 GB RAM 512 GB Memory intel I5 (4 cores) I believe I accidentally deleted an important file days ago. Since, the CPU has been riding high, unit is very warm ...
1
vote
0answers
31 views

Looking for the Kernel Debug Kit for build 18G2022?

I'm looking for the Kernel Debug Kit (KDK) for 10.14.6 build 18G2022. I see all the KDK's here, but 18G2022 hasn't been posted yet? https://developer.apple.com/download/more/?q=Kernel%20Debug%20Kit ...
11
votes
1answer
1k views

Fake ethernet interfaces (feth / if_fake)? Anyone ever seen this? [closed]

I've been digging into Darwin source to try to find some way to create virtual Ethernet interfaces on Mac/Darwin without adding a kernel extension like tuntaposx. In doing so I've found something ...
1
vote
1answer
211 views

Is the source code for xnu-6153.60.66~39 available? (iOS 13.3 Kernel)

I cannot find xnu-6153.60.66~39 at https://opensource.apple.com/tarballs/xnu/ ! Does apple still open source the XNU Kernel?
136
votes
2answers
195k views

How to investigate high kernel task memory usage?

I was using my MacBook Pro (with 16GB of RAM) as usual and out of blue I've this popup that: Your system has run out of application memory. To avoid problems with your computer, quit any applications ...
2
votes
1answer
245 views

How to make a bootable partition from scratch?

What I want to achieve is to make a new bootable partition on my MacBook's SSD, so it should be possible to press Option key on startup and choose this partition to boot from. Why do I need that? I ...
29
votes
6answers
71k views

How to disable the SpeedStep when using MacBook Pro without a battery?

First of all, the specs: MacBook Pro (15-inch, Early 2011) OS X 10.9.1 (Mavericks) 2.3 GHz Intel Core i7 8 GB RAM The Problem Recently, my battery randomly died and I had to disconnect it, ...
12
votes
2answers
3k views

How to access /dev/mem in OSX?

How I can access /dev/mem (or /dev/kmem, /dev/pmap) equivalent device in OSX? As far as I know it was removed in some point. Can I create this node manually somehow or any other way of dumping the ...
33
votes
3answers
57k views

What exactly does kernel_task do?

I'd just like to know what it is that kernel_task is responsible for. Also, what's an acceptable maximum RAM and CPU use for it?
2
votes
1answer
210 views

sysctl setting net.inet.tcp.keepidle removed in 10.15. Is there a replacement setting?

My work requires long-running connections to databases that required this sysctl setting in earlier OSX versions. Since it no longer exists, these connections appear to remain open, but they ...
1
vote
1answer
41 views

Command to release the best amount of Kernel Task and Memory Ram

I have an old MacBook Pro 2012/2013 and it has the El Capitan Through the Utilities -> Activity Monitor tool I can get the following stats according the following behavior: For example if the Mac ...
2
votes
1answer
490 views

Run Rosetta on macOS Sierra

I'm wondering if there is any way to run Rosetta on macOS Sierra. In this post, someone mentioned that Rosetta may uses the Carbon framework, which appears to exist in up to macOS Sierra. Are there ...
19
votes
4answers
11k views

Which command controls the open file limits?

Which command / configuration file controls the open file limits on OS X? Is there a different command for OS X 10.5 / 10.6 / 10.7? The options I explore below are ulimit, sysctl, and launchctl "...
53
votes
1answer
11k views

Why is macOS limited to 1064 processes?

In macOS, the system is limited to running no more than 1064 processes systemwide, and individual users are limited to 709. Why is there a limit? Why is it this size? Why not a round number like 2500 ...
3
votes
0answers
2k views

Device Console error: kernel compat_ifmu_ulist error 14

After looking through my Console log I noticed a strange error that seems to show up around 10 times a second or so. The error is coming from the kernel and shows up as one of the following 5 or so ...
1
vote
1answer
38 views

Where can I find the official documentation of macOS Kernel Debugging?

I want to study kernel debugging on macOS, and hence have tried to find official documentation for macOS Kernel Debugging. Currently, I'm only able to find up-to-date or complete information on third-...
3
votes
1answer
431 views

Kernel Panic Help - 2013 Mac Pro (Trashcan)

Been getting this k-panic once a day for the past year or so... No rhyme or reason to it, but it happens at least once a day. System slows down just a little bit, not to an unusable point, however... ...
4
votes
1answer
111 views

Does the Catalina XNU kernel still recognize 32-bit binaries? Does 10.15's dyld?

I've seen lots of commentary repeating the end result "32-bit apps are no longer supported." But that leaves many unanswered technical questions. Does 10.15's XNU still recognize 32-bit binaries? ...
1
vote
3answers
2k views

MacBook without battery kernel_task 100% CPU utilization

After removing the battery from a MacBook late 2009 following a battery fault, the computer always runs kernel_task at 100% CPU utilization. I assume the process ends up in some kind of spin lock when ...
0
votes
0answers
36 views

How to set kernel state to unbounded (“unlimited”) value using sysctl?

I want to set kern.maxfiles kernel state to unbounded value using sysctl. However, the commands sysctl kern.maxfiles=unlimited yields an error (not an integer), while I'm not sure of the sematics of ...