What is mac os kernel

Процесс kernel_task на MacOS — что это?

Если у вас компьютер под управлением MacOS (MacBook или iMac), то вы не раз замечали в «Мониторе активности» процесс «kernel_task». Что это такое и почему он грузит систему — рассмотрим в нашей статье.

Данный системный процесс может значительно грузить «железо» устройства (особенно процессор). Нагрузка сопровождается увеличением скорости работы кулеров системы охлаждения.

Что за процесс

На сайте компании Apple указано, что основная функция «kernel_task» — управление температурой за счет «подавления» требовательных к производительности программ.

Если компьютер начинает нагреваться, то процесс запускается и ограничивает работу приложения, которое вызвало это повышение температуры. Процент нагрузки «kernel_task» пропорционально зависит от нагрева.

Как отключить

Особенно беспокоит данная проблема владельцев устаревших моделей Mac (2012 и более ранние) из-за невысокой производительности самого устройства. Решить это можно удалением некоторых компонентов. Рассмотрим два варианта.

Для MacOS Yosemite и передыдущих

Если у вас версия операционной системе младше, чем El Capitan, то процесс отключения будет выглядеть следующим образом.

1. Зайдите в «Терминал» → введите по очереди две команды:
   • defaults write com.apple.finder AppleShowAllFiles TRUE
   • killall Finder

Откройте «Об этом Mac».

«Подробнее» → «Отчет о системе».

Запомните информацию с пункта «идентификатор модели» (например, «MacBookPro5,5»).

«Переход» → «Переход к папке».

Кликните ПКМ по файлу «IOPlatformPluginFamily.kext» → «Показать содержимое пакета».

«Contents» → «PlugIns» → кликните ПКМ по «ACPI_SMC_PlatformPlugin.kext» → «Показать содержимое пакета».

В «Contents» → «Resources» найдите файл с названием вашего Mac (например, «MacBookPro7,1») → удалите его.

Перезагрузите ПК → откройте «Терминал» → пропишите 2 команды:

• defaults write com.apple.finder AppleShowAllFiles FALSE
• killall Finder

Для MacOS El Capitan и новее

В новый версиях «яблочной» системы установлена защита целостности системы, которая более известна под именем «SIP». Из-за этого спсоб отличается от предыдущего.

1. Выключите Mac.
2. Во время включения зажмите комбинацию «⌘R» для вход в меню восстановления.
3. Откройте раздел «Утилиты» → «Терминал».

Введите команду csrutil disable → перезагрузите устройство.

Повторите все действия из предыдущего пункта.

Источник

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 new kernel_task pops up again until it finishes whatever it’s doing.

How can I find out what this process is doing?

12 Answers 12

TLDR; If your MacBook Pro runs hot or shows a high % CPU for the kernel task, try charging on the right and not on the left.

High kernel_task CPU Usage is due to high chassis temperature caused by charging. In particular Left Thunderbolt port usage.

• Move charging from the left to the right side. If you have a second charger then plug it in on the right side. Avoid plugging everything on the right side (see last paragraph below).
• Unplug something from the left side. Either power or another accessory until the battery is full.
• Force fans to max before plugging in. iStatMenus has an easy Sensors -> Fans menu item to do so. This only helps in marginal conditions.
• Move to a cooler room.

Proof:

Actual CPU temperature or application CPU usage is uncorrelated with kernel_task . A hot CPU is throttled by reducing its clock speed, not by scheduling fake no-op load.

The graphs below are from iStatMenus. The machine had been used on battery then plugged in.

State A a USB-C hub (a mouse and keyboard, plus power) and a USB-C HDMI 2.0 adapter, both on the left side. You can see the Thunderbolt Left Proximity temperature sensor rise quickly. About 3-4 minutes later the dreaded kernel_task high CPU usage starts.

State B cures the kernel_task problem by moving power from the left ports to the right. The left side temperature drops and the kernel_task goes away within about 15 seconds.

This is causal. Moving power back to the left side, restoring State A, quickly restores the temperatures and kernel_task again comes back after 3-4 minutes. Again moving power back to the right side, restoring State B, resolves the problem immediately.

State C shows that simply having stuff plugged in to TB ports raises their temperature significantly. Both the hub (mouse and keyboard ONLY) and HDMI adapter individually raise the temperature about 10 degrees, and 15 degrees together.

(all other temperatures were both low and flat. Under 55 degrees.)

Note that high temperature on the right side appears to be ignored by the OS. Plugging everything into the two right ports instead of the left raised the Right temperatures to over 100 degrees, without the fans coming on. No kernel_task either, but the machine becomes unusable from something throttling.

Ergo, high CPU usage by kernel_task is caused by high Thunderbolt Left Proximity temperature, which is caused by charging and having normal peripherals plugged in at the same time.

2017 15″ Macbook Pro, MacOS 10.14.5

To actually answer the question:

How can I find out what this process is doing?

The only way to actually ask the kernel what it’s doing is to attach a kernel debugger. That means getting a debug kernel from Apple, rebooting, then using a second Mac to attach to the debugged machine. You can then examine stack traces and guess what they mean.

Otherwise guessing and testing is the only way. Of course that leads to false conclusions more often than not.

Источник

Question: Q: Kernel_task High CPU Usage

I have a Mid 2015 MacBook Pro running Yosemite (10.10.5). Starting today the computer froze and took several restarts to turn back on. It now seems to be not freezing but kernel_task is using

500% of the cpu and slowing the laptop to a crawl. Rebooting in Safe Mode made no difference. http://www.rdoxenham.com/?p=259 Tried this fix but did not help.

MacBook Pro with Retina display, OS X Yosemite (10.10.5), null

Posted on Aug 9, 2016 12:37 PM

All replies

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Please post the output from EtreCheck

Aug 9, 2016 6:47 PM

EtreCheck version: 2.9.13 (267)

Report generated 2016-08-10 17:12:31

Runtime 4:04

Performance: Good

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Problem: Computer is too slow

Hardware Information: ⓘ

MacBook Pro (Retina, 15-inch, Mid 2015)

MacBook Pro — model: MacBookPro11,5

1 2.8 GHz Intel Core i7 CPU: 4-core

16 GB RAM Not upgradeable

8 GB DDR3 1600 MHz ok

8 GB DDR3 1600 MHz ok

Bluetooth: Good — Handoff/Airdrop2 supported

Wireless: en0: 802.11 a/b/g/n/ac

Battery: Health = Normal — Cycle count = 329

Video Information: ⓘ

AMD Radeon R9 M370X — VRAM: 2048 MB

Color LCD 2880 x 1800

System Software: ⓘ

OS X Yosemite 10.10.5 (14F27) — Time since boot: less than an hour

Disk Information: ⓘ

APPLE SSD SM0512G disk0 : (500.28 GB) (Solid State — TRIM: Yes)

EFI (disk0s1) : 210 MB

Macintosh HD (disk0s2) / : 349.36 GB (338.51 GB free)

Recovery HD (disk0s3) [Recovery]: 650 MB

BOOTCAMP (disk0s4) /Volumes/BOOTCAMP : 150.05 GB (32.31 GB free)

USB Information: ⓘ

Apple Internal Memory Card Reader

Apple Inc. Apple Internal Keyboard / Trackpad

Broadcom Corp. Bluetooth USB Host Controller

Thunderbolt Information: ⓘ

Apple Inc. thunderbolt_bus

Gatekeeper: ⓘ

Mac App Store and identified developers

System Launch Agents: ⓘ

[not loaded] 4 Apple tasks

[loaded] 155 Apple tasks

[running] 53 Apple tasks

System Launch Daemons: ⓘ

[not loaded] 46 Apple tasks

[loaded] 139 Apple tasks

[running] 76 Apple tasks

Other Apps: ⓘ

[loaded] 367 Apple tasks

[running] 148 Apple tasks

Internet Plug-ins: ⓘ

Default Browser: 600 — SDK 10.10 (2015-07-17)

QuickTime Plugin: 7.7.3 (2016-08-10)

3rd Party Preference Panes: ⓘ

Time Machine: ⓘ

Time Machine not configured!

Top Processes by CPU: ⓘ

Top Processes by Memory: ⓘ

955 MB kernel_task

393 MB com.apple.WebKit.WebContent(3)

213 MB mdworker(12)

Virtual Memory Information: ⓘ

10.00 GB Free RAM

5.52 GB Used RAM (2.69 GB Cached)

Diagnostics Information: ⓘ

Aug 10, 2016, 05:02:07 PM Self test — passed

Aug 10, 2016, 09:01:22 AM /Library/Logs/DiagnosticReports/com.apple.AddressBook.InternetAccountsBridge_20 16-08-10-090122_[redacted].crash

/System/Library/Frameworks/AddressBook.framework/Versions/A/XPCServices/com.app le.AddressBook.InternetAccountsBridge.xpc/Contents/MacOS/com.apple.AddressBook.I nternetAccountsBridge

Aug 10, 2016 9:13 AM

You have a very clean system. That is good, but it also makes it harder to figure out exactly what is happening.

Experiment #1. Quit Safari and see if the CPU usage goes back to normal. It is possible there is some JavaScript running on one of the web pages you have open that is asking the system to do things on its behalf. This is an easy experiment.

Experiment #2. Rebuild your Spotlight index.

NOTE: Until the Spotlight index is completely rebuilt, it is going to chew up some CPU and I/O bandwidth. So do not go looking right away after starting the rebuild.

Aug 10, 2016 10:36 AM

There are several reports of this problem with Yosemite.

There are various «fixes» around the internet.

This provides a good summary of the problem and things to try:

If that doesn’t help, there is everyone’s favorite fix.

This proposed fix is kind of scary.

Aug 10, 2016 11:58 AM

I wiped the hard drive and reinstalled a fresh install of the OS, hence the cleanliness, but the problem persists. Tried both your suggestions with no change. Could it possibly be a hardware problem?

Aug 11, 2016 4:33 AM

I’m guessing that maybe you are still within your 1 year warranty, so at the minimum you might want to make a Genius Bar appointment at your local Apple Store. With your system in a totally clean state it would be ideal to avoid any finger pointing at 3rd party products.

Note: I do not know why a high kernel task CPU usage would be caused by a hardware problem, but surprising things happen all the time.

Another experiment. Boot into Safe mode

This would load only Apple drivers, and some of them less optimized, to see if that changes anything. I’m not expecting much, but again, it is an easy experiment. You would not want to run full time in Safe mode, but as an experiment it is useful.

I think one of the rccharles links had resetting the SMC and PRAM. If you did not do that yet, then also try those.

By any chance are you in the middle of FileVault encryption (or decryption) and that is what is occupying the kernel task? Then again, a clean install should not have a lot on the system, so it should complete in a reasonable amount of time. Also I would only expect FileVault encryption to occupy just 1 CPU or 100% not 500%. You can check FileVault encryption status with the following Applications -> Utilities -> Terminal command

diskutil cs list | grep Conversion

Those all my ideas for this morning.

Aug 11, 2016 5:56 AM

Note: I do not know why a high kernel task CPU usage would be caused by a hardware problem, but surprising things happen all the time.

The author of internet article I found thought that a hardware problem could invoke the high cpu. Although, it was dealing with some external device.

Aug 11, 2016 8:42 AM

Thanks for the help, I have tried all your suggestions with no luck. I was trying to avoid getting it sent off but I think I have no other choice now.

Aug 12, 2016 2:51 AM

Did you send it off/fix it?

I had this issue on another model (2011) macbook running 10.11.06. Turned out to be dusty fans. CPU throttling due to overheating. I thought it was buggy OS after a recent upgrade and i saw all the threads on resets and moving files around but saw one guy saying it was a symptom of the system trying to slow heat production.

I checked the fans first before anything else and they were mildly caked, seems like in the three weeks since i last had it open after a logic board replacement, it’s picked up a year or two’s worth of muck. removed them, paint brush, bit of blow dryer and reassembly and all is good again and much quieter. gone from 670%CPU back down to 5-3%

hope maybe this helps

Aug 21, 2016 3:39 PM

I seem to have solved the kernel_task PCU drain using this method I stumbled across on the web.

1. Go to About this mac under the apple in the upper left and click on More info

2. Click on system report

3. make a note of what it says after Model Identifier

4. go to your master drive – System -Library – Extensions – IOPlatformPluginFamily.kext -Contents – Plugins – ACPI_SMC_PlatformPlugin.kext – Contents – Resources – find the name from step 3 and move it to a folder that you can find again if needed.

3. Restart and you’re done

I hope this helps.

Nov 24, 2016 7:43 PM

Thanks ntson28. It has solved my problem.

Mar 20, 2017 8:29 PM

Hello, i am having the same issue as elliot 😟 I did SMC, VRAM, Diagnostic, First Aid, safe mode reboot and nothing works. i did the entrecheck but i don’t know how to analyze this, seeing the eset. Would you kindly have a look and let me know please? Thanking you in advance!

EtreCheck version: 3.1.5 (343)

Report generated 2017-04-04 19:46:29

Runtime 11:27

Performance: Poor

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Problem: Computer is too slow

Description:

kernel_task is taking so much memory and my fan is running high, its also getting hot.

Hardware Information: ⓘ

MacBook Pro (Retina, 15-inch, Mid 2015)

MacBook Pro — model: MacBookPro11,5

1 2.5 GHz Intel Core i7 (i7-4870HQ) CPU: 4-core

16 GB RAM Not upgradeable

8 GB DDR3 1600 MHz ok

8 GB DDR3 1600 MHz ok

Bluetooth: Good — Handoff/Airdrop2 supported

Wireless: en0: 802.11 a/b/g/n/ac

Battery: Health = Normal — Cycle count = 235

Video Information: ⓘ

AMD Radeon R9 M370X — VRAM: 2048 MB

Color LCD 2880 x 1800

22MP55 1920 x 1080 @ 60 Hz

System Software: ⓘ

macOS Sierra 10.12.4 (16E195) — Time since boot: less than an hour

Disk Information: ⓘ

APPLE SSD SM0512G disk0 : (500.28 GB) (Solid State — TRIM: Yes)

[Show SMART report]

EFI (disk0s1) : 210 MB

Recovery HD (disk0s3) [Recovery]: 650 MB

Macintosh HD (disk1) / [Startup]: 499.07 GB (72.17 GB free)

Core Storage: disk0s2 499.42 GB Online

USB Information: ⓘ

Western Digital My Passport 259F

Apple Inc. Apple Internal Keyboard / Trackpad

Broadcom Corp. Bluetooth USB Host Controller

Thunderbolt Information: ⓘ

Apple Inc. thunderbolt_bus

Gatekeeper: ⓘ

Mac App Store and identified developers

Unknown Files: ⓘ

/Library/Application Support/mediahm/mediahm.app/Contents/MacOS/Installer -evnt agnt -oprID 80801048|00106|1000011|0|0|1|0|000000000|27012016|00222190|MA==|bm9uZQ==|QUU=|V W5pdGVkIEFyYWIgRW1pcmF0ZXM=|

One unknown file found. [Check files]

Kernel Extensions: ⓘ

/Library/Application Support/ESET/esets/PlugIns/kext

[not loaded] com.eset.kext.esets-kac (6.1.12 — SDK 10.6 — 2016-04-12) [Support]

[not loaded] com.eset.kext.esets-mac (6.1.12 — SDK 10.6 — 2016-04-12) [Support]

[not loaded] com.eset.kext.esets-pfw (6.1.12 — SDK 10.6 — 2016-04-12) [Support]

/Library/Extensions

[loaded] com.intel.kext.intelhaxm (6.0.3 — SDK 10.9 — 2017-04-01) [Support]

[not loaded] com.wacom.kext.ftdi (1.0 — SDK 10.10 — 2017-04-01) [Support]

[not loaded] com.wacom.kext.wacomtablet (Wacom Tablet 6.3.13-3 — SDK 10.10 — 2017-04-01) [Support]

System Launch Agents: ⓘ

[not loaded] 7 Apple tasks

[loaded] 183 Apple tasks

[running] 92 Apple tasks

System Launch Daemons: ⓘ

[not loaded] 40 Apple tasks

[loaded] 171 Apple tasks

[running] 107 Apple tasks

Launch Agents: ⓘ

[not loaded] com.adobe.AAM.Updater-1.0.plist (2017-03-14) [Support]

[failed] com.adobe.ARMDCHelper.cc24aef4a1b90ed56a725c38014c95072f92651fb65e1bf9c8e43c37a2 3d420d.plist (2017-01-13) [Support]

[running] com.adobe.AdobeCreativeCloud.plist (2017-03-31) [Support]

Launch Daemons: ⓘ

[loaded] com.adobe.ARMDC.Communicator.plist (2017-01-13) [Support]

[loaded] com.adobe.ARMDC.SMJobBlessHelper.plist (2017-01-13) [Support]

[running] com.adobe.adobeupdatedaemon.plist (2017-03-31) [Support]

[running] com.adobe.agsservice.plist (2017-03-10) [Support]

[loaded] com.adobe.fpsaud.plist (2017-03-01) [Support]

[not loaded] com.intel.haxm.plist (2016-06-12) [Support]

[loaded] com.macpaw.CleanMyMac3.Agent.plist (2017-03-30) [Support]

[loaded] com.microsoft.autoupdate.helper.plist (2016-12-22) [Support]

[loaded] com.microsoft.office.licensing.helper.plist (2016-10-29) [Support]

[loaded] com.microsoft.office.licensingV2.helper.plist (2015-08-07) [Support]

[loaded] jp.co.canon.MasterInstaller.plist (2016-05-07) [Support]

User Launch Agents: ⓘ

[loaded] com.adobe.AAM.Updater-1.0.plist (2017-01-14) [Support]

[loaded] com.google.keystone.agent.plist (2017-03-30) [Support]

[not loaded] com.macpaw.CleanMyMac3.Scheduler.plist (2017-04-04)

[not loaded] com.mediahm.operator.update.plist.eset (2016-04-12) [Support] —

/Library/Application Support/mediahm/mediahm.app/Contents/MacOS/Installer: Executable not found!

[not loaded] jp.co.canon.Inkjet_Extended_Survey_Agent.plist (2015-02-12) [Support]

User Login Items: ⓘ

iTunesHelper Application (2017-03-30)

CleanMyMac 3 Menu Application Hidden (2017-03-02)

(/Applications/CleanMyMac 3.app/Contents/MacOS/CleanMyMac 3 Menu.app)

AdobeResourceSynchronizer Application Hidden

(/Applications/Adobe Acrobat DC/Adobe Acrobat.app/Contents/Helpers/AdobeResourceSynchronizer.app)

[redacted]’s Public Folder Folder

Sony Ericsson Bridge Helper Application Hidden

/Library/Application Support/Sony Ericsson Bridge for Mac/Sony Ericsson Bridge Helper.app)

Internet Plug-ins: ⓘ

QuickTime Plugin: 7.7.3 (2017-04-01)

AdobePDFViewerNPAPI: 15.023.20056 — SDK 10.11 (2017-01-22) [Support]

AdobePDFViewer: 15.023.20056 — SDK 10.11 (2017-01-22) [Support]

SharePointBrowserPlugin: 14.7.0 — SDK 10.6 (2016-12-13) [Support]

PepperFlashPlayer: 25.0.0.127 — SDK 10.9 (2017-03-29) [Support]

WacomTabletPlugin: WacomTabletPlugin 2.1.0.6 — SDK 10.9 (2015-07-09) [Support]

3rd Party Preference Panes: ⓘ

Time Machine: ⓘ

Skip System Files: NO

Mobile backups: ON

Auto backup: YES

Volumes being backed up:

Macintosh HD: Disk size: 499.07 GB Disk used: 426.90 GB

Satellite Samurai [Local]

Total size: 500.09 GB

Total number of backups: 1

Oldest backup: 9/1/16, 1:09 AM

Last backup: 9/1/16, 1:09 AM

Size of backup disk: Too small

Backup size 500.09 GB Top Processes by CPU: ⓘ

11% Microsoft Outlook

11% Google Chrome Helper(13)

5% Google Chrome

Top Processes by Memory: ⓘ

2.37 GB Google Chrome Helper(13)

1.36 GB kernel_task

623 MB Microsoft Outlook

492 MB mdworker(17)

262 MB Google Chrome

Virtual Memory Information: ⓘ

9.56 GB Available RAM

2.16 GB Free RAM

6.44 GB Used RAM

7.39 GB Cached files

Diagnostics Information: ⓘ

Apr 4, 2017, 07:24:31 PM Self test — passed

Apr 4, 2017, 08:41:56 AM /Library/Logs/DiagnosticReports/Adobe InDesign CC 2017_2017-04-04-084156_[redacted].hang

/Applications/Adobe InDesign CC 2017/Adobe InDesign CC 2017.app/Contents/MacOS/Adobe InDesign CC 2017

Apr 4, 2017, 08:38:12 AM

/Applications/Adobe Photoshop CC 2017/Adobe Photoshop CC 2017.app/Contents/Frameworks/AdobeCrashReporter.framework/Versions/A/AdobeCRDae mon.app/Contents/MacOS/AdobeCRDaemon

Apr 4, 2017, 08:33:17 AM /Library/Logs/DiagnosticReports/Adobe InDesign CC 2017_2017-04-04-083317_[redacted].hang

Apr 4, 2017, 08:21:29 AM

/Library/Logs/DiagnosticReports/Adobe InDesign CC 2017_2017-04-04-082129_[redacted].crash

Источник