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HYPER-THREADING
TECHNOLOGY
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Abstract
Hyper-Threading technology was first introduced on the Intel Xeon
processors.
In November 2002, Intel launched this technology on the Intel Pentium 4
at clock frequencies of 3.06 GHz and higher, making the technology
widely available to the consumer market.
This Technology brings the concept of simultaneous multithreading to the
Intel architecture. It describes how Intel made a single physical processor
appear as multiple logical processors.
Users can get a 25-percent boost in performance from a technology that
costs less than 5 percent in added die area.
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Abstract
This Technology illustrate the importance of choosing the right sharing
policy for each shared resource.
This is done by examining and comparing three different sharing
policies they are partitioned resources, threshold sharing, and full
sharing.
The choice of policy depends on the traffic pattern, complexity and size
of the resource, potential deadlock scenarios, and other considerations.
Finally, it describes how this technology significantly improves
performance on several relevant workloads.
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Contents
Introduction Problem statement
Existing System
Proposed System
Advantages of current system
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Introduction
Hyper-Threading (HT) Technology is ground breaking technology from
Intel that allows processors to work more efficiently.
This new technology enables the processor to execute two series, or
threads, of instructions at the same time, thereby improving performance
and system responsiveness while delivering performance for the future.
Intel Hyper-Threading Technology improves the utilization of onboard
resources so that a second thread can be processed in the same
processor.
Hyper-Threading Technology provides two logicalprocessors in a single
processor package.
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Introduction
Basics Of Hyper-Threading Technology:
Intel's Hyper-Threading Technology duplicates certain sections of the
processor, specifically those areas that store the CPU's architectural state
and not the main execution resources.
By processing only the architectural state, Hyper-Threading is able to
make the processor appear as if dual processors are available.
As this process occurs, Hyper-Threading allows the operating system to
schedule two threads or processes simultaneously through each processor.
The technology utilizes simultaneous multithreading and is used to increase
both throughput and energy efficiency
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Introduction
Working Of Hyper-Threading Technology:
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System Architecture
Processors without Hyper-Threading Tech Processors without Hyper-Threading Tech
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Problem Statement
The amazing growth of the Internet and telecommunications is powered by
ever-faster systems demanding increasingly higher levels of processor
performance.
To keep up with this demand we cannot rely entirely on traditional
approaches to processor design.
Microarchitecture techniques used to achieve past processor performance
improvement. In fact, transistor counts and power consumption are
increasing at rates greater than processor performance.
Processor architects are therefore looking for ways to improve performance
at a greater rate than transistor counts and power dissipation.
Intels Hyper-Threading Technology is one solution.
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Existing system
Using more than one processor in a system directly provided thread levelparallelism. But this was a costly solution and required special on board
support for multiple processors.
These systems also required some type of synchronizing mechanism. The
overhead for this synchronizing and the frequent collision for the need of
resources slowed down such implementations considerably.
Hyper-threading, introduced by Intel provided by Intel provided the
solution for this problem, but also provided its own challenges.
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Proposed System
Hyper-Threading is Super-threading without the restriction that eachpipeline stage or clock cycle must contain instruction form the same thread.
Vacant execution slots in each pipeline stage is filled by instruction from
another thread, enabling thread level parallelism.
This can be done as long as there is no collision of resources required by
two threads.
In processors with Hyper-Threading Technology, a single processor core
executes these two threads concurrently.
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Advantages of Current SystemBy using Hyper-threading Technology the advantages are:
Improved overall system performance.
Increased number of users a platform can support.
Improved reaction and response time because tasks can be run on separate
threads.
Increased number of transaction that can be executed.
Compatibility with existing IA-32 software.
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Conclusion
IntelsHyper-Threading Technology brings the concept of simultaneous
multi-threading to the Intel Architecture.
This is a significant new technology direction forIntels future processors.
It will become increasingly important going forward as it adds a new
technique for obtaining additional performance for lower transistor and
power costs.
Intel Xeon Hyper-Threading is definitely having a positive impact on Linux
kernel and multithreaded applications.
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