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Questions tagged [hyperthreading]

In a hyperthreaded CPU, for each processor core that is physically present, the operating system addresses two virtual or logical cores, and shares the workload between them when possible.

In an hyper threaded environment, For each processor core that is physically present, the operating system addresses two virtual or logical cores, and shares the workload between them when possible.

This allows to decrease the number of dependent instructions on the pipeline. It takes advantage of superscalar architecture (multiple instructions operating on separate data in parallel).

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Processing speed of a core with hyperthreading

If a processor has a specified base frequency and number of threads it supports, what is the frequency that each thread really gets to utilize? For instance, the Intel® Core™ i7-4500U Processor has 2 cores and 4 threads with a base frequency of 1.80…
asdfvar
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Fast Loopback on Windows 10 with weird HyperThreading results

I have successfully enabled SIO_LOOPBACK_FAST_PATH option on Windows 10 even though there isn't much information on whether Windows 10 supports it. Here is some info on the feature link1 link2 I have a basic TCP server and client using send()/recv()…
Harry
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Why does a node.js application on Heroku perform identically with 2 threads vs. 4?

I've been working on a series of automatic load-testing scripts, and I've noticed that when averaged out, there's no difference between running a cluster of 2 processes and 4 processes on a Heroku dyno (in this case, a Hapi.js server which just…
ThreeHams
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Max CPU usage (max allowed CPU usage)

I have a quad core (with hyper threading Technology - HT) I'm running an application which takes 270% CPU (according to TOP command) What is the total available CPU usage? (is it 400% or 800%?) I'm asking because according to Intel documentation,…
user3668129
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Hyper-threading, Multi-threading, Multi-processing and Multi-tasking - Theory

I am confused on the different terms as to their actual differences. What are each of them and what do they actually mean? My IT teacher at school gives us one definition the one day, and another the next, so please can you shed some light for…
user3241507
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Level of Parallelism present in multiple threads per core

So i have been looking into some of the technologies that implement multiple threads per core (like intel's hyperthreading) and I am wondering whats the extent of parallelism in these kinds of technologies. Is it true parallelism or just more…
PandaRaid
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Why is parallel compilation performance with HT worse than without?

I've made several measurements of compilation time of wine with HyperThreading enabled and disabled in BIOS on my Core i7 930 @2.8GHz (quad-core) on Linux 2.6.39 x86_64. Each measurement was like this: git clean -xdf ./configure --prefix=/usr time…
Ruslan
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Hyper-Threading and CPU-bound processes

So I'm running a cpu intensive task that isn't parallelized on my i7 laptop. KSysGuard reports that I'm using 12.5% of the available cpu. If I disable hyper threading am I likely to get a meaningful performance increase? It'll require flashing a new…
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hyperthreading and turbo boost in matrix multiply - worse performance using hyper threading

I am tunning my GEMM code and comparing with Eigen and MKL. I have a system with four physical cores. Until now I have used the default number of threads from OpenMP (eight on my system). I assumed this would be at least as good as four threads. …
user2088790
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Is there a task scheduler that is well-suited for floating-point calculations on processors with hyper-threading?

I would like to use TPL to manage calls into Intel IPP or MKL libraries. Naturally, these are floating-point compute-intensive instructions. Since Hyper-Threading only assigns one floating-point thread per core, I'd like a way to schedule tasks…
GregC
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How to make maximum benefit from Hyper-Threading in .Net

Not sure if that is even possible in a managed language, but is it possible to actually make an application perform better in the presence of hyper threading ? Is there something specific that can be done in the code ? , maybe some functions run…
sharp12345
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How to make my i7 processor reach 100% usage with this code (fastest way to parse xml)

How to make my i7 processor reach 100% usage with this code? Is there something special that happens in the XmlDocument? is just because of the context change? and if so why putting more threads wouldnt make the the processor use its full power?…
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How to implement affinity on multi-core HT with topological considerations in a C++ program?

I'm developing some C++ multi-core programs with a variable number of threads and I'd like to know how to set a proper (actually "the best") affinity. I use Boost-threads, so I can call get_hardware_concurrency() to know how many logical cores there…
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Does Visual Studio build time benefit much from hyperthreading?

I'm looking at getting an i7-3770 to replace my i5-2500K in my aged 1155 LGA based PC. Clock speeds are quite similar, and Ivy Bridge was a fairly small improvement over Sandy Bridge microarchitecturally. The main boost I'd get is 4 additional…
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What is the difference between Hyperthreading and Multithreading? Does AMD Zen use either?

I read that the multithreading is the feature that a single core can manage many threads (not in parallel) and the benefit is that the CPU is always working. For the Hyperthreading that a single core create 2 Virtual Cores and take 2 Threads for…
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