A multi-core CPU is a kind of CPU that has two or more actual chips inside it (known as cores). This allows a computer to actually be processing multiple things at once and is often seen as the solution to continuing Moore's law.

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How many instances of FFmpeg commands can I run in parallel?

I tired running 8 commands in parallel to fully utilize the CPU and speed up Video conversions, something like this: ffmpeg -i input.mp4 -t 60 -f mp4 /mnt/a.mp4 > /dev/null 2>&1 & ...
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4answers
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How do multi-core CPUs work?

I know, vague question title, but my main question is, does 1 core have to execute only one program at a time? Does the "multitasking" at the CPU level work by switching between tasks, and if so, why? ...
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240 views

Does the OS exploit multiple cores

I know that more cores isn't always better and that most applications are single threaded however does the OS make use of the additional cores? For example, assume an application such as a dictionary ...
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1answer
340 views

Is it faster to run one process that spawns N threads or to run N processes?

I need to run ~1500 jobs on my lab's server. The program I am using (blastpgp if anyone cares) is capable of running in parallel mode, the "-a" option sets how many threads it will launch. The server ...
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2k views

Can a single process be executed in two or more processors in a multiprocessor system?

I have heard that one processor can work on only one process at a time. Is this true? If so, then how can a single process be executed in more than one processors at a time? Is this even possible? ...
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1answer
388 views

6-core Sandy Bridge-E vs. 4-core Ivy Bridge [closed]

I am currently choosing between Intel Core i7-3770 (quad, Ivy) and Intel Core i7-3930K (6 cores, Sandy Bridge-E). This machine will be used for both work (Adobe, Autodesk software, graphic and ...
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3answers
833 views

Running threads on a non hyper-threading Intel processor

Intel Pentium Processor E5700 (2M Cache, 3.00 GHz, 800 MHz FSB) does not have hyper-threading but it has has 2 cores so I am assuming it has 2 threads Now if I write a heavy number crunching program ...
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1answer
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disable hyperthreading on a multi-core Dell PC

I have a Dell desktop running Windows 7 Professional. I think the processor is an Intel Core i7-2600 Recently a computer expert who specializes in Linux clusters was looking at my desktop PC and ...
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2answers
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vmWare Player - virtual machine configured for 2 CPUs but I only have 1 CPU

I copied a virtual machine that I downloaded but can't play it in vmWare player. When I start to play it, it says: This virtual machine is configured to run with 2 CPUs, but the host has only 1 ...
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0answers
42 views

need advice on hardware for doing parallel processing

We are intending to buy a powerful workstation for our daily processing of some seismic data. The process consists of doing numeric processing on data acquired on different seismic stations and by its ...
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3answers
11k views

Windows 8 task manager: single-core CPU graph only?

On multi-core CPU systems, Windows 7's task manager used to display a separate utilization graph for each core unit: On Windows 8 the task manager looks much fancier, and yet it shows a single ...
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457 views

Efficient way to use all cores in bash or zsh script

If I want to process large number of files with command "do_something" which only can use one core, what's the best way to use all available cores assuming each file can be processed independently? ...
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1answer
195 views

Setting process affinity in Linux

In Windows, it is possible to make a program run on any number of cores in a multicore processor. It can be set in the Task Manager GUI. Likewise, Is it possible to set the process affinity in Linux, ...
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1answer
517 views

Core i3 3220 for gaming [closed]

Since the Core i3 3220 has Hyper-Threading, will games like Battlefield 3 see and use the CPU as a virtual "quad core" rather than just 2 physical cores, so that AI and other features in the game run ...
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1answer
756 views

How do the cores in an AMD Bulldozer module compare to Intel HTT virtual cores and two separate cores, in terms of multitasking performance?

This question is basically an extension of Hyper-Threading and Dual-Core, What's the Difference? The Bulldozer-based AMD FX processors are marketed as having four, six, or eight cores, but ...
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0answers
371 views

Does VMWare Fusion (5) use logical CPU cores before physical ones?

I have a Intel Core i7 quad core CPU in my Mac Book Pro. The processor supports hyperthreading, so I have 4 physical CPU core and 8 logical ones. Now, when I assign 4 CPU cores to a virtual machine ...
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1answer
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Why is the “top” command showing a CPU usage of 799%?

I am running a process in a 4 core Ubuntu server. However, top command shows that the CPU usage is 799% all the time. How can this be possible? I know for multi core CPUs, more than 100% CPU usage ...
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3answers
479 views

Will multicore allow the same CPU usage as multi CPU [duplicate]

Possible Duplicate: Multi-core CPU: can I say I have a 3x2.1GHz=6.3GHz CPU? I plan to buy latop with with i5-2410M processor that have 2 cores (according to spec it can also have 4 ...
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4answers
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Do multi-core CPUs still suffer from diminishing returns in today's world?

It has been shown in other questions that due to the state of computer applications, multi-core processors suffer from diminishing returns. Is this still the case in today's world? Do most new ...
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2answers
789 views

Terminology used for CPU/Processors

Suppose a system has 4 Intel Xeon processors each having 10 physical cores with HyperThreading enabled which makes a total of 80 cores Now it is completely confusing when in documentation they start ...
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2answers
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Why is my Dell Vostro 3500 overheating? The internal temperature is around 75 C

I felt that my Vostro laptop is overheating. I downloaded a tool named SpeedFan to test my internal laptop temperature. Speedfan gives the following measurements: Temp1: 75 C Core0: 70 c Core1: ...
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1answer
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“Steal” cores to other users: reduce user's processes priority

I'm working on a shared linux machine with multicores where I do have admin rights. Is it possible to freeze all the processes of other users (or give them less priority to access to the CPUs) so that ...
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2answers
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What is the effect of booting with additional cores?

I was reading about ways to enhance speed in Windows 7, and I read that you can enable Windows to boot off of four cores vs one to boot faster. Is there a reason why you do not want to use all four ...
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4answers
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Multi-core CPU: can I say I have a 3x2.1GHz=6.3GHz CPU?

I have an AMD A6-3500 three-core CPU. AMD System Monitor shows each core with a maximum 2100 MHz. This also shows in AMD OverDrive. Does this processor run at the speed 3*2100 MHz? Edit Can I say ...
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1answer
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Single-threaded program takes too low CPU?

I am using Windows 7 Professional, Intel i7 CPU. I know the i7 has Hyper-Threading and I assume this is the reason. While running a single-threaded program, I saw that it only uses 12-13% CPU in Task ...
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0answers
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Have anybody tested R multicore packages on 10-core Xeon how do they scale in comparison with case of 4 core machine?

Have anybody tested R multicore packages (for example : parallel, multicore, snowfall, foreach) on 10-core Xeon ? How do they scale in comparison with case of 4 core machine ? What algorith have you ...
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1answer
888 views

Ubuntu not balancing cpu usage among cores, making load go up

I am running 10 processes that each use 20-70% of a core of an i7-920 with 8 cores on Ubuntu 11.04. CPU scaling is turned off. When I look at htop, I see that cores 4 and 8 are almost unused, while ...
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1answer
189 views

How are benchmarks for multiple cores calculated? [closed]

I found this site to compare CPU's. http://www.cpubenchmark.net/high_end_cpus.html What wasn't clear is how the benchmark for multiple core processors is calculated. If one CPU has 4 cores (such as ...
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0answers
844 views

Dynamically disabling cores in a power-efficient way?

I am looking for a mechanism to dynamically disable cores in Linux in order to minimize power consumption. Unfortunately, disabling cores using the following simple approach actually increases power, ...
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1answer
1k views

How can I tell my computer to use multiple cores for gaming? [duplicate]

Possible Duplicate: Force a single core program to use multi core Whenever I play games (specifically Minecraft) on my computer, only one of the cores is being used to run the game, which ...
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2answers
653 views

Finding the number of Cores on my CPU in GNU/Linux

When I do cat /proc/cpuinfo I get the folowing information printed below. Can I conclude from this information that there are 8 cores in my machine? I am interested in doing some parallel programming ...
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1answer
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shared L2 in multicore: regarding miss per kilo instruction (MPKI) counting

I am using multicore simulator marss http://marss86.org. I am using 4-core simulation, with shared L2 cache. Each core is run for say, 100M instructions. Since different cores progress at different ...
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2answers
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How do you get more cores?

Are you able to gain cores? I bought The Elder Scrolls V: Skyrim without looking at the specs. I need at least a dual core processor but I only have a single core processor.
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1answer
2k views

Windows BSOD when all cpu cores enabled

I'm getting a blue screen "A clock interrupt was not received on a secondary processor within the allocated time interval", just a few seconds after the Windows desktop is loaded. (For reference, ...
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1answer
1k views

How can I configure Visual Studio 2008, so that it uses multiple cores for compile?

I use Visual Studio 2008 on a bigger project. If some files get compiled, it compiles them one after the other. My computer has 8 cores, except one they are idle. How can I configure Visual Studio, ...
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1answer
393 views

Why does top report more than the theoretical maximum CPU usage of a machine?

I would like to know why I have a process being able to report a usage line like: PID COMMAND %CPU 248 Xcode 983.5 … in top on a quad core CPU? I understand it's wrong, but how come? I'm ...
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2answers
619 views

How does a multi core computer freeze (at the hardware level)

I have a 4 core i7 computer that freezes. The display stays, but nothing will ever move again. This question is not about getting help on that particular problem, but a general question about how a ...
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0answers
2k views

Should I prefer processor speed (GHz) or core count? [closed]

I'm currently in the market for a new computer, so I'm curious about the recent trends of processor speed versus core count. Core count seems to be 'all the rage' these days, but things are really ...
2
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1answer
221 views

What are “multikernel computers”?

Which does the term 'modern multikernel computers' refer to? Distributed systems or multi-core computers? I saw it in a one-line question, so no context to help! Google didn't help neither.
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1answer
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Is Windows 7 better at utilizing multi-core processors than Windows xp?

Is Windows 7 better at utilizing multi-core processors than Windows xp? Better to have some explanation and proofs with the answer(yes or no).
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2answers
556 views

Does adding core to multicore CPU mean increasing the transistor count? [closed]

I'm studying Moore's law. I'm curious why many people say Moore's law ends, so we switch to multicore CPU. From all materials I can find, I understand this by such logic: increasing clock rate -> ...
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1answer
1k views

What are “hyperthreading” and “virtual cores”?

I'm new in this computer terms. So anyone can explain to me what "virtual cores" and "hyperthreading" are at greatest detail a layman can understand? People told me that virtual cores are imaginary ...
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266 views

Clock frequency, number of cores , threads

I'm really confused. What determines the speed of the CPU/processor? Some compared a dual core with 2.8ghz and a 2.4ghz quad-core and say the quadcore is better. But when it comes to a dual core ...
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5answers
9k views

Why is my dual-core CPU recognized as a quad-core one?

My processor is an Intel Core i3-380m. As you can see, it's 2 cores and 4 threads. Although, both Ubuntu 11.04 and Windows 7 seem to think it's a quad-core CPU: Why is this? Is it because there ...
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5answers
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Is a higher core count or higher clock speed more beneficial to a computer's performance? [closed]

With lowering silicon costs and rising consumer needs, manufacturers seem to be pushing one of two things: clock speed and/or core count. With the way things are going, it doesn't seem that clock ...
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2answers
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How to make commands in Mathematica 8 use all cores?

Many commands in Mathematica 8 (Integrate, Simplify, etc.) seem to only be using a single core on my system. Is there any way I can change the affinity so that it utilizes all cores for computations?
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Binding interface per core

I just wonder, is it possible (using Linux 2.6) to limit overhead done by ethernet interface to one specific core. Ie. I have core2duo CPU, and two ethernet interfaces: eth0 and eth1. Is it possible ...
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/proc/cpuinfo gives CPU info per core or per thread?

My CPU has 2 cores, so I can see two parts in /proc/cpuinfo. But, I want to know if CPUs that support Hyper-Threading (or similar tech), will /proc/cpuinfo give CPU info per core or per thread (or ...
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1answer
175 views

What's a dual core? [duplicate]

Possible Duplicate: Can someone clear up the terms Core Duo CPU, Quad Core, Dual CPU, etc.? Does "core" mean CPU or memory or both? I'm thinking of buying a new computer. But ...
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How to limit a process to a single CPU core?

How do you limit a single process program run in a Windows environment to run only on a single CPU on a multi-core machine? Is it the same between a windowed program and a command line program? ...