Tagged Questions

A technology by Intel to increase processor throughput, by adding independent logical processing units in each core (and thus exposing two times the number of cores to the operating system).

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0answers
19 views

Advantage of Hyperthreading when we have OOO

I was reading about SMT and it says that when a thread is executing and one thread is waiting for say memory access and we will execute the next thread. So what possible advantage will it bear when we ...
0
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2answers
50 views

do I get half the CPU speed for a single thread if HT is turned on? [duplicate]

If I have a single 2.6GHz core for example would it mean that with hyperthreading I have only 1.3GHz for a single thread that my app have or is it on demand only if I will use (lets say my app is the ...
0
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1answer
37 views

Cores and threads - Performance

I wonder if a 4 core/8 thread cpu will perform better than a 4 core/4 thread cpu. If the answer is yes; How much better will a 4/8 perform? EDIT: What if its for running 4 single threaded apps? And ...
0
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1answer
66 views

CPU usage drops dramatically

I am using an engineering software to conduct series of computationally demanding analyses. I have a relatively powerful desktop with the following specs: CPU: Intel core i7 3930k @ 3.2GHz RAM: 64 GB ...
1
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0answers
115 views

See if Mac OS X has enabled hyperthreading?

There is a way of disabling hyperthreading on Mac OS X: How to disable HyperThreading on Mac OS X Lion? Is there a Terminal command of seeing whether Mac OS X has hyperthreading enabled?
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3answers
2k views

What is the difference between multithreading and hyperthreading? [closed]

I've heard the terms hyper-threading and multi-threading, but what exactly is the difference between them? What kind of inlet processor uses them?
0
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2answers
175 views

Again about Hyper Threading

I have Asus 1025c with dual-core atom with hyper-threading enabled. When I play games, processor load rate always less than 25% (1 core). Is that means, that game (running single thread) occupies only ...
0
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0answers
61 views

Does Windows know how to appropriately assign threads to a quad-core processor that has Hyper-Threading on?

So, I have been trying to google for this answer, but I cannot find a direct technical answer to the question. (Or if it did, it was in a confusing way) So, say you have a program/game that uses 2 ...
2
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1answer
318 views

How to interpret this /proc/cpuinfo data?

I'm using Intel Xeon E5-2620 processor. These are something I'm confusing about. I'm using Linux and in /proc/cpuinfo it says model name : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz According to the ...
2
votes
1answer
899 views

Quad Core host with hyper-threading, how many processors to configure in VirtualBox?

I have a quad-core i7 processor with hyperthreading (8 logical cores), when I configured a virtual machine to use 8 processors, VirtualBox gave me a warning saying that I only have four cores (which ...
5
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2answers
3k views

Single Threaded Qaud Core v.s Hyper-Threading Dual Core

Let's say we have two CPUs, One is Quad Core 3.2 Ghz with 4 Cores, and We have a Dual Core 3.2 Ghz with 2 Cores with 2 threads in each Core (Hyper-Threading). My assumption as a programmer will be, ...
0
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1answer
41 views

Hyperthreading load

Would loading all threads on a hyper-threading enabled cpu (e.g. core i7 dual core with 2 threads per core) be (in this case) double the load the cpu? To clarify, lets say I have a dual core cpu with ...
-2
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1answer
139 views

How does a CPU with 2 core or more works and hyperthreading

I got a little confused,when there is 2 cores or more to a CPU does it mean that two processes can run on those cores or two different threads?.When there is hyper-threading does two threads run the ...
15
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3answers
2k views

Task Manager is saying the system is running with over a thousand threads

I opened up Task Manager and looked under the "System" area and saw: Threads: 1337 Since I have a dual-core processor with hyper-threading available (meaning four threads), how is it possible to ...
2
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1answer
1k views

cpu load measure with hyperthreading on linux

How can I get the true usage of a multicore hyperthreading enabled cpu? For example lets consider a 2 core CPU, expressing 4 virtual cores. A single threaded workload would now show up as 100% in ...
0
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2answers
293 views

Hyperthreading Calculating Load [duplicate]

I have a dual core core i5 with hyperthreading. Since hyperthreading allows for unused cpu time to be used by other processes, why would this make it seem like 4 logical processors (2 per actual ...
0
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1answer
67 views

How can I decide real vs virtual cores if i need intensive calculus?

Assume that I have a computer called A with a processor that has two cores and has hyperthreading, i.e it has 2 cores with 4 threads (I understand that this can supply to 4 processes simultaneously), ...
3
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2answers
1k views

Hyper Threading vs Overclocking

What is the difference between these two, and under what circumstances would I want to implement them? Are there circumstances when I would only want 1 and not the other? According to Wikipedia, ...
0
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0answers
75 views

Pstate (underclock) on single core hyperthreaded cpu

In Ubuntu, I can underclock the CPU using the CPU freq applet. My netbook is a Intel atom n270, basically single core with 2 "virtual cores" due to hyperthreading. I can underclock one of these ...
2
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3answers
810 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 ...
1
vote
1answer
5k views

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 ...
0
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1answer
202 views

Does hyperthreading divide GHz in half?

Imagine you have a CPU with 4 cores @ 2.2GHz, each one with a thread. Therefore, the OS thinks that it has 8 cores @ 1.1GHz each (I think). What would be the maximum GHz that a not concurrent ...
1
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2answers
726 views

Optimum number of threads to use for best parallel processing on an i5 [closed]

I'm interested in running some reasonably heavyweight processing on my desktop/laptop (not so bad that it requires a cluster, but needs a good home machine). My question is how many threads to create ...
0
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1answer
33 views

Duplication of Architecture State means physically extra?

Hyper-Threading Technology makes a single physical processor appear as two logical processors; the physical execution resources are shared and the architecture state is duplicated for the two logical ...
0
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1answer
516 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 ...
2
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2answers
5k views

How to disable HyperThreading on Mac OS X Lion?

Unlike my old Windows Boxes and Linux Boxes, I do not have access of something similar to a BIOS on my MacBook Pro. I want to disable Intel i7's HyperThreading (so 4 cores look like 4 cores and don't ...
0
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3answers
838 views

Disable Hyper-Threading on Dell XPS L502x

Does anyone know how, or if it's even possible, to disable Hyper-Threading on an Dell XPS L502x? I've checked the BIOS, which seems like it's hiding a lot of the usual options, but can't see ...
2
votes
0answers
502 views

Disable hyperthreading on MacPro Xeon

We need to disable hyperthreading on several MacPros. We have just two types of Macs - Dual QuadCore 2.4 "Westmere" and single CPU SixCore 3.66 "Westmere". All machines run 10.6.8 For some strange ...
1
vote
1answer
1k views

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 ...
0
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1answer
132 views

Is this processor burned?

I've recently exchange the processors in two PCChips boards. Both boards are LGA775. Board A is P17G(Pentium 4 HyperThreading 3GHz) and board B is P49G(Pentium Dual Core 3GHz). I use board A to watch ...
3
votes
1answer
761 views

Eclipse: would more CPU cores with HyperThreading help increase speed?

I'm programming a very large project in Eclipse. Right now I use a dual core machine with 2GB RAM, but Eclipse is sometimes busy for minutes (refreshing/indexing/building), so I'm upgrading to a new ...
0
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1answer
262 views

What happens to HyperThreading when I throttle the state on battery power?

If I have a laptop with an i7 that I decide to throttle the maximum processor state to 50% on battery power, what happens in regard to HyperThreading? Does it get activated at 50% frequency? or does ...
4
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2answers
5k views

CPU monitoring: hyper threading, current clock speed

I think it'd be interesting if it were possible to check out at how much Ghz each one of my cores is running. Is it possible, at all?
2
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1answer
582 views

Does the i5 processor in the 2011 iMac allow hyper threading?

On the intel website, it says that the i5 processor uses hyper threading. Elsewhere on the internet I've read various conflicting reports. Can anyone give me a definitive answer?
3
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2answers
2k views

Is there a significant performance difference between virtual and real cores? [duplicate]

Possible Duplicate: Hyper-Threading and Dual-Core, What's the Difference? Most Intel processors feature what they call "hyperthreading," basically another virtual core for each physical ...
14
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3answers
5k views

How does Windows processor affinity work with hyperthreaded CPUs?

How does Windows processor affinity work with hyperthreaded CPUs? Let's use an example (pictured) of a system with four cores, each with a hyper-threaded virtual core. Which cores correspond to each ...
2
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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 ...
47
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5answers
8k 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 ...
3
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2answers
7k views

/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 ...
11
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3answers
18k views

Disable Hyperthreading in the Windows 7 registry

Some bios's Do Not have the option to disable Hyperthreading of the CPU, it there a way to disable it in the Windows 7 Registry? Or a tool or software? I know about msconfig boot tab (advanced ...
3
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2answers
12k views

How to query Intel® Hyper-Threading current state and how to enable/disable it?

How can I see if my IntelĀ® Hyper-Threading is enabled or disabled on my Windows 7?? There is a way to change it?
7
votes
2answers
1k views

I have some kind of 4-core Intel CPU. How to I switch it back to dual core?

I have a laptop with Intel i5 M430 2.27GHz. The CPU has TWO REAL cores but it also has some kind of virtualization so Windows sees it as 4-core. In a REAL dual core CPU, a single threaded program ...
26
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4answers
5k views

How much speedup does a hyper thread give? (in theory)

I'm wondering what the theoretical speedup is from hyper threaded CPUs. Assuming 100% parallelization, and 0 communication - two CPUs would give a speedup of 2. What about hyper threaded CPU?
5
votes
1answer
6k views

Number of cores available to VMware Player limited to physical cores or hyperthreaded cores?

I have an i7 with 2 physical cores, because of hyper threading Windows 7 reports 4 cores (at least in the Task Manager). My question is, when allocating cores to a VM in VMWare Player is it taking ...
0
votes
1answer
368 views

Full HD and hyperthreading

I have 3 GHz Pentium 4, and it's not best for playing full HD videos. I noticed, that when I'm playing full HD video, only 50% of my cpu is used, so only one of virtual cores is doing it's job on full ...
0
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2answers
991 views

How to disable HT in a Intel Atom D425?

I can't find in the BIOS the option to disable HT. Is this a BIOS problem or the processor itself doesn't support running as a single core?
1
vote
1answer
1k views

VirtualBox recognise all threads as cores or only physical cores for dual core Core i7?

When I run VirtualBox (or other virtualisation software) it lets me select how many cores I like to allocate to a virtual machine. Since I have a dual core 2.66gHz Intel Core i7 with hyperthreading, ...
27
votes
2answers
15k views

Hyper-Threading and Dual-Core, What's the Difference?

In a conversation with the network administator, I mentioned that my machine was a dual-core. He told me it was not. I brought up the task manager, went to the perfomance tab, and showed him that ...
3
votes
3answers
2k views

How can a single threaded application like Excel 2003 take more than 50% of a hyper-threaded or dual-core CPU in task manager?

I'm waiting for Excel to finish a recalculation and I notice that the CPU usage as reported by Task Manager occasionally spikes to 51% or 52% on a Pentium 4 with hyper-threading. How is a ...
20
votes
3answers
9k views

What is hyper-threading and how does it work?

I've heard the term hyper-threading thrown around a bit recently, what exactly is hyper-threading and why is it important?