The CPU (Central Processing Unit) is the part of a computer that performs tasks instructed by the computer programs. Its role is somewhat analogous to that of the human brain; it performs simple mathematical, logical, and in/out operation of the machine.

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418 views

What causes the UserEventAgent to run with 100% CPU usage?

Since about a month, my MBPr sometimes starts up it’s fans and is getting really hot. The activity monitor tells me, that this is because of the UserEventAgent, which runs with 100% CPU usage. This ...
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2answers
868 views

Get cpu usage per core on the command line

Activity monitor allows users to see the cpu usage on a per-core basis (for multicore machines, e.g. my MacBook Pro). Is there a way to find the percent usage of each core/processor via the command ...
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4answers
4k views

Retina MacBook Pro running very hot?

I have a late-2013 Retina MacBook Pro, and it gets really hot really easily. I've monitored the temp with htop and iStat and they both show the same readings. It's supposed to be able to play some ...
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2answers
61 views

How does my dual core i5 in my MacBook Pro have more than 400% CPU usage?

I've got the Early-2015 13" MacBook Pro (2.7 GHz i5) and whilst I was building Smart Previews for all my 1600+ photos in Lightroom 5 I noticed that the fan had come on (unusually) and that the laptop ...
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1answer
49 views

cpu is 100% used, yet no application shows significant usage

Since a few days my IMac started showing weird behaviour. In Activity Monitor it shows that my CPU is 100% used. Literally 0% idle, but there are no Applications using anywhere near this much ...
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1answer
22 views

Memory/CPU usage comparison between two MacBook Pros

I recently switched from a 2014 mid MacBook Pro Retina with 2.7 GHz and 8 GB of RAM to a 3.1 GHz and 16 GB of RAM. I noticed something very strange which is that 1) when I am dong very basic tasks ...
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1answer
19 views

Mac Pro 4,1 CPU upgrade

I own a Mac Pro 4,1 (single socket) with a Nehalem Quad-Core CPU. I'd like to upgrade it with a six-core Westmere processor. Now, what I have to do prior to installation of the Westmere processor? ...
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2answers
163 views

Check if G5 is a SMP one?

How do I check if a G5 PPC mac has 2 CPUs or not? When booting it up under Linux (Debian 8) only one CPU seems to be detected: cat /proc/cpuinfo processor : 0 cpu : PPC970FX, altivec ...
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1answer
25 views

Limit CPU when starting a task in terminal

I'm working on an application for part of a school project that simulates an operating system and which I launch using the Terminal. By nature it will consume all possible resources to loop over and ...
8
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1answer
12k views

VTDecoderXPCService taking CPU

Sometimes I notice CPU load for no reason and I see in Activity Monitor that VTDecoderXPCService is using 15-30% of CPU. After I restart Safari it is ok for some time until it happens again. Any ...
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0answers
17 views

How to make sense of >100% CPU usage and re-spawning of a force-quitted process?

My MBP was making loud noises again so I opened up my activity manager and I was baffled to see that the CPU usage of mutt is more than 100%. This is strange because all I was doing in it was to ...
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1answer
821 views

My CPU is running slow after a system restore (4x0.8 GHz). Turbo Boost is definitely not working. And how can I fix it?

Last weekend, my Macbok Air suffered a heart attack and I ended up doing several hard shutdowns due to an unresponsive system. In the end I had to do a full system restoration. Everything is working ...
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0answers
18 views

Diagnosing cooling issues on MacBook Air

I suspect the fan on my 2011 MacBook Air is not cooling efficiently, as it runs over 5000 RPM when I'm browsing the web and the CPU is around 75% idle. Is there any published benchmark for what the ...
0
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1answer
43 views

MacBook Pro 13" 2015 CPU and GPU temperatures

I've noticed that my new MacBook Pro 13" 2015 (MF839) is getting hot while playing browser games or watching models at sketchfab.com. Both CPU and GPU temperatures rise to 100-105 degrees (Celsius) ...
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votes
1answer
2k views

iPhone: What is `accountsd` and why is it using 80% CPU?

I just got a new iPhone 6 for my SO and noticed that it is quite toasty to handle with the battery draining quite fast. It has been 24 hours since I first set it up. I plugged it into Instruments ...
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7answers
10k views

High CPU time of Finder in El Capitan

I have extremely high CPU time for Finder use after updating to El Capitan version 10.11.0 I've tried: Rebooting the Mac Resetting SMC Resetting NVRAM The machine is borderline unusable with ...
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vote
1answer
86 views

High CPU and energy usage in Safari

Energy impact of Safari is extremely high on my Macbook Air Mid 2013 El Captian 10.11.2. It lead to high usage of CPU (Temperature ~65.0°C) and the CPU fan is running in full speed (6500.0 RPM) ...
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0answers
68 views

Is it possible to disable CPU throttling on a MacBook Pro with a completely dead (not recognized) battery?

I have a MBP late 2011 running El Capitan, recently my battery died (x over the icon and "no battery available" in the dropdown.) I've noticed since then that CPU intensive tasks are very slow, and I ...
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2answers
206 views

What is “usernoted” and why is it eating my CPU?

For the past couple of weeks, a process identified as usernoted appeared to "take over" my machine after a few hours of use, eating over 99% of available CPU. Force quitting the process doesn't help; ...
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2answers
16 views

Is a “2 GHz Intel Core Duo” really the same as a “2 GHz Intel Core ***2*** Duo”

I'm trying to get Sling TV set up on an older iMac. It has 10.6 (the minimum required OS), 2.5 GB RAM (~2.5 times the required memory), and a 2 GHz Intel Core 2 Duo. However, the Sling TV web ...
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votes
5answers
23k views

“powerd” process uses a lot of CPU

Oftentimes, after I wake my Mac from sleep, powerd (which is the power management daemon? Which in particular deals with sleeping the Mac and waking it?) uses high CPU, usually around 25% to 50% on my ...
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2answers
10k views

mdworker process always at 100%, even when not indexing

I'm trying to understand why mdworker is always at 100% even when (apparently) not indexing. If I open Spotlight, there's no message telling me that a drive is being indexed. If I run fs_usage -w -f ...
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votes
2answers
390 views

Macbook Pro 15“ vs 13” - Performance vs portability

Currently I've got a MacBook Pro 15" (mid-2010, model 6,2), with 8 GB RAM, 2,5 GHz i5 Processor and Intel HD Graphics 288 MB video card. Seeing as it's 5+ years old, I really need a new one, ...
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98 views

High CPU usage when Your iCloud session has expired

I have had this problem here: El Capitan: Your iCloud session has expired In addition to this I noticed that iTunes is using nearly 100% of the CPU and the fans go crazy. After logging and fixing ...
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3answers
25k views

View the current clock Speed of a CPU in OS X?

Does anyone know of a utility to see the current speed of the processor? To be clear, I'm not looking for the model/speed of the CPU, but rather what the CPU is currently clocked at (i.e. it will ...
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2answers
3k views

CPU usage is too high with Yosemite and an external monitor

I use Yosemite 10.10.4 on my MacBook Pro (2012). I used to work with an external monitor: Apple Thunderbolt 27" monitor. The issue is that, according to Activity Monitor, the kernel_task process ...
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votes
1answer
307 views

Brand new MacBook Pro flagship behaving strangely

Today i got the newest available MacBook Pro flagship model. After setting up some basics, installing Photoshop, JRE, XAMPP and NetBeans, i started to use the machine a bit, doing some basic coding. ...
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0answers
92 views

excessive cpu usage from kernel_task after accidentally ripping Facetime HD camera connector off the logic board

Accidentally ripped off the Facetime HD camera cable of the logic board. Now whenever I boot into OS X kernel_task hogs all the cpu (500%). I could be wrong here, but my hunch is that because no ...
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6answers
21k views

Why is the accountsd process eating so much CPU?

Why are the accountsd and securityd processes using so much CPU on OS X 10.10.3? I am on a Early 2011 Macbook Pro. What are these processes for? Is it safe to kill them? The machine has only been up ...
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1answer
120 views

“Wi-Fi” process in OSX El Capitan uses a lot of CPU

"Wi-Fi" process takes a lot of CPU almost all the time. Why is it happening, and how to fix it?
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2answers
2k views

Safari on OS X Yosemite 10.10.4 CPU problem

Since a couple of days I have problems with the CPU usage of my Safari installation. It runs on OS X Yosemite 10.10.4 (MacBook Pro 13" from 2011). To reproduce it I only have to open one empty tab ...
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0answers
64 views

Macbook Air thinks it's overheating

Recently my Mid-2013 macbook air began to act like it's overheating. Upon boot the cpu fan almost immediately spins up to 100% (over 6000 rpm) and the cpu heavily thermal throttles. I am positive the ...
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votes
3answers
2k views

Finder sidebar flashing text and high CPU load since El Capitan

After update to OS X 10.11 I started having these bugs: Finder sidebar text flashing Video Very high CPU load: I have Macbook Pro Retina 13" Mid 2014 I reset NVRAM. I deleted ...
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2answers
33 views

Anyway to add new processor to MacBook 5,1 or MacBook Air 204

I'd like to add a faster processor to my MacBook Air 2014 or my MacBook 5,1 unibody. Is this possible at all?
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votes
3answers
931 views

Acceptable CPU usage for 4 core 3.4gHz i7

Creating a kiosk application for the Mac and am testing performance and CPU usage. The activity monitor shows a total of roughly 90 to 150% CPU usage for the always up, kiosk processes. My first ...
3
votes
2answers
2k views

kernel_task hundreds of % CPU yet cpu frequency is being lowered

I'm trying to solve the mystery of a crazy high cpu usage on kernel_task. MacBook Pro (Retina, Mid 2012), 2.7 GHz Intel Core i7, Yosemite 10.10.2 I saw some advice to download the Intel Power ...
5
votes
2answers
1k views

CPU Pushed to Too Much Usage by kernel_task

I have a Macbook Pro Retina with the following hardware: Model Name: MacBook Pro Model Identifier: MacBookPro11,1 Processor Name: Intel Core i5 Processor Speed: 2.4 GHz Number of Processors: 1 ...
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1answer
32 views

Increase Activity monitor update frequency to less than a second

I want to use the "CPU history" to monitor how some program uses the CPU, but the update frequency of "very often (1 sec)" is not fast enough for me. The changes I want to observe happen in less than ...
0
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1answer
28 views

Is there any more way to squeeze out some performance out of my mid 2009 Macbook Pro 13"?

I still like my mid 2009 13" Macbook Pro. It's solid and running quite well. However, since Yosemite things are getting really laggy and slow, so I guess that my hardware is getting a bit old. ...
0
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2answers
3k views

Apple Thunderbolt or HDMI for external monitor

Is there anybody who can answer me this question? I have a Macbook Pro Retina 15" quad i7 etc and I use some programs/applications wich need a lot of cpu and also the macbook heats up like hell. I ...
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0answers
248 views

Why does my Macbook Pro get very hot at seemingly random times? Possibly Safari-related?

I have a late-2014 15" MBP with max specs running 10.10.3, and it usually has no problem handling most of what I throw at it (running multiple resource-intensive apps at once, editing large files in ...
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0answers
263 views

How to monitor and control thermal CPU throttling in OS X?

I recently came across the Intel Extreme Tuning Utility for Windows. I tried it under Bootcamp Windows and it was very interesting to learn in what situations my MacBook Pro's (mid2012) CPU is doing ...
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0answers
66 views

Verify Intel Speedstep active with sysctl

I want to verify that Intel Speedstep throttling is indeed inactivated in my OS X 10.9.5 Mavericks MacBook Pro (2009) system. I used the Rhys Oxenham method from 2012. Unfortunately I can't run Intel ...
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1answer
253 views

Does the Apple Watch have more processing power than a Cray 2 Supercomputer?

I remember growing up in the 80's and my parents would be astounded that the Commodores and Apple II's of the time would be as powerful as a computer that used to take up a room. (I didn't quite get ...
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2answers
1k views

Background processes periodically eat up my CPU time on OS X 10.10.4, Yosemite

Periodically the CPU on my iMac Mid-2015 running OS X 10.10.4, gets used almost exclusively by: launchd: ~70% fseventsd: 12% UserEventAgent: ~40% opendirectoryd: 20% notifyd: 12% I have tried ...
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0answers
12 views

Are CPU temperatures over 110 something to worry about? [duplicate]

I am primarily a Java developer and love using OS X and Mac as my primary development environment. However recently I have been having temperature and heat concerns. I have a piece of code that ...
0
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1answer
41 views

Low Battery Performance - Activity Monitor Shows Faults in CPU statistics

My Macbook battery (I guess batteries is the more correct term in this new Macbook) isn't getting battery life as estimated by specs, and it is already lessened in only about 2 months. Today, I ran a ...
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1answer
1k views

How to disable HyperThreading on Mac OS X Yosemite?

I read that on previous versions of OS X it was possible via hwprefs but I didn't figure out how to use it on 10.10.* (looks like it was removed). I need to disable HyperThreading for Wineskin.
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votes
2answers
6k views

Very high kernel_task CPU usage after updating to Yosemite 10.10.4

I updated to 10.10.4 on July 1, and ever since I've had very high CPU usage - roughly 270%, i.e. two and a half of four processors - by kernel_task. It appears on login for about five minutes, then ...