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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What is the new turbo boost in the MacBook line?

The new MacBook line has a new turbo boost added to the processor: What exactly does this mean? From what I've heard, the processor can runs above the clocked speed for a short period of time. ...
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Troubleshooting high CPU activity in the WindowServer process

As far as I know WindowServer process is used by all apps to draw windows that we see. And a lot of people are reporting a problem when their WindowServer is using a lot of CPU. Is there any way to ...
13
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Why is my Mac's CPU throttled? (Turbo Boost Ratio)

AnandTech has a instructions1 on how you can check the Turbo Ratios for the Mac's CPU. Since they are logged, the information is very easy to find. In Mountain Lion you can do this the following ...
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Why does SystemUIServer cause high CPU usage?

The SystemUIServer process is taking 30% of my CPU. Searching around reveals a Snow Leopard daylight savings bug which is solved by removing the clock from the menubar. I am on Lion and I have tried ...
11
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1answer
26k views

What is the InterCheck process that occasionally uses 96% CPU on my Mac?

I heard my computer's fan spinning fast, so I checked Activity Monitor and saw that a process called InterCheck was using close to 96% CPU. What is this process and why's it using so much CPU? In the ...
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Dock on MBP Retina is using 80% CPU

The Dock on my MBP Retina is constantly using 70 - 80% of CPU. This happens on the two account on the machine, both of which were migrated from my previous Lion MBP. I don't have Parallels ...
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1answer
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Why does Apple Activity Monitor report that my Mac with a dual-core Intel i5 Ivy Bridge CPU has 4 cores?

I just got a new Apple MacBook Pro 13", mid-2012, which has a dual-core Intel i5 Ivy Bridge CPU. When I run Activity Monitor and turn on the Floating CPU Window, it shows a 4-bar graph (indicating 4 ...
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4answers
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How can I simulate having a slow CPU?

I am almost done coding my webapp-game. It runs on all modern browsers. However, I want to establish some minimum requirements for it. Thus, I need a slow Mac. However, I don't have access to a slow ...
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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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How many cores does a Mid 2012 Macbook Air have?

I checked the specs, and the i5-3427U CPU has 2 cores. But the Activity Monitor shows 4 little charts for the CPU, so it looks like 4 cores. Which is correct? Why does the Activity Monitor have 4 ...
5
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597 views

Make Spotlight indexing use less CPU?

Whenever spotlight begins indexing my files, my computer's fan starts spinning like crazy. Is there any way to essentially tell spotlight that it doesn't need to finish as quickly as possible, and ...
5
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1answer
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mds and mds_stores constantly consuming cpu

mds and mds_stores are constant CPU consumers even when I think nothing should have changed on the hard drive. activity monitor I have a circa 2009 Macbook Pro. Lots of software installed over the ...
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3answers
707 views

What is the Mac equivalent of Windows' Power Plans' Maximum Processor State?

One of my favorite features in Windows is the built-in Power Plans. I can change how much energy my computer uses - whether I want it to drain power like there's no tomorrow and get incredible ...
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5answers
579 views

How can I put heavy load on my CPU for a long period of time?

How can I put my CPU under very high pressure for a long period of time? Are there programs for that that I can keep running ?
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3answers
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Should I be worried about 98°C CPU temperature on MacbookAir?

I'm a developer and often times I need to compile some packages or maybe even run some codes for couple of hours. Recently I have noticed that whenever I use Homebrew to install something, it ...
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0answers
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nsurlstoraged and CPU usage

Since yesterday nsurlstoraged is constantly using a huge amount of CPU. Nothing shows up in the logs but opensnoop shows that the process is accessing ...
4
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2answers
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iTunes now takes up 100% of CPU since updating to 11.3

UPDATE: The issue seems to be at least related to what konqui mentioned in the Comments since I do have a large library of podcasts. However, if this was merely related to re-indexing then one would ...
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2answers
4k views

Process “ubd” high CPU usage

I noticed my MBP got really slow, which must be strange with SSD and 8GB of RAM. So I opened the Activity Monitor to discover a process called ubd keeps its CPU usage very high, about 120% most of ...
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0answers
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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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2answers
198 views

Changing CPU frequency policies in OS X

I have Core i5 processor with nominal 2.3 Ghz speed. But, according to Intel Power Gadget, most of the time the frequency is much lower. Even during intensive usage. It's 0.8-1.6 Ghz. I noticed that ...
2
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2answers
180 views

How to see which CPU is on the current macine?

I'm looking on the Safe Cflags on the Gentoo Wiki, and I want to figure out how to see which CPU is on a specific machine. On Gentoo I see you can get this with cat /proc/cpuinfo but on Mac I ...
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4answers
10k views

MacBook Pro CPU temperature is over 90 degrees while playing video

I have MacBook Pro: 13-inch, Late 2011 2.4 GHz Intel Core i5 4 GB 1333 MHz DDR3 Intel HD Graphics 3000 384MB OS X Lion 10.7.4 When it plays a video, the CPU temperature goes over 90 ...
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4answers
3k views

Limit processor speed like in Windows

In Windows (Linux too), you have the very useful "Power saver" mode that limits the maximum frequency at which your CPU runs. Is there something similar in OS X?
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2answers
330 views

How long can my MacBook Pro sustain greater than 100% CPU usage?

The Activity Monitor app says my macbook pro 10.7.5 is at 300% CPU usage when I'm trying to install and sync my Bitcoin-Qt client. I let in run like this with the fan going crazy for 4 hours without ...
2
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1answer
539 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 ...
2
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1answer
350 views

Mac mini 2011 mid - temperature issue

I have a mid-2011 Mac mini with an Intel i5 2.3 GHz processor. When I checked the temperature, it was 90 degrees Celcius. The computer was running for three days. It didn’t work on anything. Is this ...
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Macbook Pro 15 mid 2012 - not able to solve overheating

I've been trying to solve my overheating problem for quite a long time, but had no luck, so I will try to describe it to you and hopefully, someone can come up with some solution. I've also read ...
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1answer
2k views

What are safe CPU temperatures ranges under heavy load in the unibody Macbook Pro?

I noticed that under heavy CPU load, the temperature differences between the CPU and CPU heatsink are very high: picture from iStatPro; 2.0 GHz quad-core i7 (2635QM) Sandy Bridge; Macbook Pro 8.2 ...
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1answer
111 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 ...
2
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0answers
467 views

How does Parallels' CPU and ram usage work? When to shutdown virtual machine?

I run Windows 7 using Parallels in host operating system OSX. I have it configured to use 2GM ram and 2 cores on a Retina MacBook Pro with 8GB ram. I'm curious under what conditions I will experience ...
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2answers
1k views

kernel_task is using 90% CPU, what could be the cause?

I have a 13" MBP late 2009, 2.53 GHz, 4 GB RAM, and on OS X 10.8.3. As soon as I boot up the fans start going at the highest rpm and like I mentioned the kernel_task is always at around 90% when no ...
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0answers
113 views

Figure out which app is using Java

If I check my activity monitor there is an instance of java that is constantly taking 5% CPU or more. I know that there is some app that are using java on my system and therefore my question is: Is ...
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0answers
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Why is Mail.app using so much CPU with gmail and Exchange?

My Mail.app is configured for Gmail and Exchange. For some time now the program has been running out of control. It's pretty much constantly burning 100% of CPU (but only 100%). It's got an ...
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2answers
1k views

Do MacBooks slow down when not connected to power?

I recently read about a device that reported its "minimum CPU speed" (which was 50MHz; max was 1500MHz) and I wondered if my MacBook Air (and other devices like iPhone/iPad) slows down the CPU when ...
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2answers
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What's the difference between real memory and CPU, and what are there effects on the performance of my computer?

In Activity Monitor, there are a couple fields: "PID", "Process Name", "User", "%CPU", "Threads", "Real Mem", and "Kind". I'm not familiar with the inner workings of computers and the related ...
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2answers
2k views

Excessive CPU usage from sysmond

Does anyone know what the sysmond application does on OS X? Lately it has been taking about 25-30% cpu constantly for no apparent reason. Things I've tried so far: Reboot SMC reset PRAM reset ...
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2answers
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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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1answer
462 views

How do I fix enourmous CPU usage & temperature on MacBook Air when trying to install Wine?

I have a 2012 MacBook Air Intel Core i5 8 GB memory (Mountain Lion). I am trying to install Wine through MacPorts, but after about a minute of building Wine, CPU usage rapidly rises into the 90s, and ...
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1answer
39 views

Does Apple design its own CPUs?

We're having a little debate here at work. Does Apple design its own CPUs? And by CPU design I mean what is on Wikipedia. I'm also interested to know the manufacturers of Apple's CPUs/SoC (maybe ...
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2answers
814 views

MacBook Pro Retina, questions about 2nd monitor for gaming

I have a MacBook Pro Retina, and I'm gaming a lot with bootcamp windows 8. I'm considering buying a external monitor for better gaming (might be a BenQ, has to be 120Hz). My questions: Does a 2nd ...
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2answers
2k views

Possible to chain mac minis together?

Is there a guide to extending a mac mini by adding several mac minis together to add cpu and memory capacity?
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3answers
3k views

What is causing the high system CPU load under Mountain Lion?

I recently began to see some odd behavior on my MacBook Pro on Mountain Lion. I noticed the fans coming up and applications behaving sluggish. I checked the ActivityMonitor (see below) and the ...
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1answer
1k views

CPU upgrade on MacBook Pro

I'm thinking about upgrading the CPU in my MacBook Pro from its current 3210M dual core processor to a 3632QM quad core processor. Is there any reason why this wouldn't be a good idea? The socket, ...
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1answer
164 views

/usr/bin/nice and Handbrake

This is really two questions... If a process is run with nice (/usr/bin/nice in the default OS X Mountain Lion installation) will it run processes in equivalent time compared to that process being run ...
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1answer
446 views

How to limit cpu frequency in OS X?

The OS X kernel does control this directly since below 5% my CPU gets locked to 1.2GHz instead of the normal 3.7GHz so there has to be a way to control the CPU speed. I am aware of this question ...
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1answer
184 views

CPU at 100%, but no processes showing significant usage

Situation: All 4 cores maxed out. Mac noticeably lagging. Attempted Solution: (Reveals wildly contradictory information.) Closed all applications Opened Activity Monitor Totaled all Process ID ...
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1answer
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OSX High CPU Usage

Are the following CPU usages normal?? From last few days my macbook air is heating too much. And i frequently notice the fan running fast. Top two process have always use over 70% cpu and it goes to ...
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1answer
445 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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1answer
2k views

MBP early '11 kernel_task over 300% when unplugged

Ok, after reading so many topics and not finding a solution maybe I should join the army of people posting topics about a kernel_task problem with a MBP. Which MacBook do I own: MacBook Pro 13", ...
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1answer
26 views

Mountain Lion — Finder always freezing

I'm on 10.8.2. Finder always freezes. I have way more CPU and memory than this OS needs. It's only Finder. CPU usage spikes, spinning beachball, the whole thing. I cleared all my caches, disabled ...