What is Hyper-Threading? A Look at Intel's Newest Multithreading Technology

What is Hyper-Threading?

Hyper-threading is an Intel technology that improves CPU performance by enhancing the parallelization of computations, allowing a CPU to perform more tasks at the same time since more work can be performed in parallel. Many of Intel’s latest CPU offerings come equipped with Intel Hyper-threading technology. For example, Intel Core processors, Intel Core vPro processors, Intel Xeon processors, and Intel Core M processors all support Intel Hyper-threading technology. You do not have to do anything to take advantage of Intel Hyper-threading technology as it comes enabled by default on systems that support it. 

Hyper-threading works by splitting each physical CPU core into two logical cores known as threads, improving the efficiency of the CPU. CPU efficiency is improved because hyper-threading enables multiple instructions to operate on separate data in parallel. A CPU with hyperthreading enabled will display two logical cores for every physical core the CPU has, allowing the system to direct each logical processor to execute a specific thread independent of the other logical processor. For example, an Intel 10900K with 10 cores will display a total of 20 CPU threads, boosting the system’s performance. That said, for a computer system to take advantage of hyper-threading, both the operating system and BIOS must support simultaneous multithreading, and hyper-threading must be enabled. Hyper-threading is usually enabled by default, so there is nothing you have to do to take advantage of this technology. 

Hyper-threaded CPUs are different from multi-core processors, which have multiple physical processors on a silicon chip. This is so because the logical processors on a hyper-threaded CPU core share the same execution resources, such as cache, execution engine, and system BUS interface. Sharing of resources is beneficial because if a logical processor is stalled, such as when it’s waiting for data, the other logical processor has the ability to take advantage of the remaining resources, allowing the system to utilize each physical CPU core to the max. This increases processor throughput, improving the overall performance of the system. Intel even claims that hyper-threaded CPUs perform up to 30% better than the same CPUs with hyper-threading disabled. 

Intel’s hyper-threading technology benefits include running complex, demanding applications simultaneously on a system, improving system responsiveness and efficiency, enabling users to complete tasks more quickly, providing faster response times for applications, and providing some headroom for future business growth. Of course, the performance boost gained by enabling hyperthreading largely depends on how optimized the operating system and software is to take advantage of hyper-threading technology. Poorly optimized applications will not benefit, as will applications that are optimized to take advantage of Intel Hyper-threading technology. 

How Can You Enable Hyperthreading? 

To enable hyper-threading, you must have a CPU with the feature and your motherboard must also support it. If both the motherboard and CPU support hyper-threading, the feature will be enabled by default. That said, if, for any reason, the feature is turned off, you can enable it by heading over to your BIOS and setting the feature to enabled. Likewise, if you want to turn off hyperthreading, you can do so from your system’s BIOS settings by toggling the feature to the disabled mode. With hyperthreading disabled, each core will show up on your OS as only having a single thread. 

Why is Hyperthreading Important? 

Hyperthreading is important because it allows users to take full advantage of their CPU under certain conditions. This is so because often, a CPU has to fetch data or programming instructions from memory, and the few millionths of a second that it takes for the computer to fetch this information is plenty of time for the CPU to execute dozens of instructions. So, hyper-threading uses this brief interval of time to run instructions from another thread, providing a boost in performance since no time is wasted and CPU computing power is fully utilized. 

CPUs with Hyper-threading vs. CPUs Without Hyper-threading 

A CPU with hyper-threading allows more than one thread to run on each core. The more threads that are added, the more work a CPU can finish in parallel. On the other hand, a CPU without hyper-threading only contains one execution context that can handle a single software thread. For example, a CPU with hyper-threading enabled will show up on a system as having two logical cores for every single physical core, allowing each physical core to handle multiple software threads in parallel. Two logical cores can handle tasks more efficiently than a single-threaded core because the CPU can take advantage of idle time when the core would be waiting for other tasks to be completed. Intel even claims that users can expect CPU performance to be improved by up to 30% with hyper-threading enabled. 

What is the Difference Between Single-Threaded Applications and Multi-threaded Applications? 

With a single-threaded application, the execution of instructions is contained in a single sequence, meaning that one command is processed at a time. However, with multi-threaded applications, the execution of instructions is in multiple sequences, allowing the system to execute multiple parts of the program at the same time. Simply stated, multithreading is a form of parallelization that allows an application to divide work for parallel processing. So, instead of providing a single core with a large workload, the workload of multi-threaded applications is split into multiple software threads, allowing multiple CPU cores to process threads in parallel. That said, to take advantage of multithreading, the software or application you’re running must be multi-threaded.  

What Are the Benefits of Hyper-threading? 

If you have a system that includes a CPU that supports hyperthreading, you will notice that your computer is able to process more information in less time than when hyperthreading is disabled. Additionally, when hyper-threading is enabled, your system will be able to run more background tasks without causing a disruption to your workflow. This is possible because hyper-threading allows each of your CPU’s physical cores to perform two tasks at once. This offers great benefits to multi-taskers and professionals running heavily threaded applications.  

Do All Intel Processors Come with Hyper-threading? 

No, not all Intel processors come with hyper-threading. For example, new Intel Xeon processors come with hyper-threading technology. Intel Atom processors come with and without hyperthreading. When it comes to Intel Core processors, some come with hyperthreading and some without. Usually, you will find hyper-threading on i7 and i9 processors, while some i3 and i5 processors do not come with hyperthreading. 

Should You Enable Intel Hyper-threading? 

If you have a CPU and motherboard that supports hyperthreading, you should definitely enable it. This is so because Intel claims that a single socket system, hyperthreading can offer a performance boost of up to 30%, and it costs you nothing to enable the technology. In fact, most manufacturers that sell systems equipped with CPUs that support Intel Hyper-threading technology recommend that users keep hyper-threading enabled as part of their best practices. This is so because the technology does provide a performance boost for your system. If you want to check whether your system supports hyper-threading technology, head over to your BIOS and look for the term “Intel Hyperthreading Technology.” If the feature is set to disabled, toggle it to enabled, and you should begin to enjoy what this technology has to offer.  

Does Microsoft Windows Support Hyperthreading? 

Yes, Microsoft Windows is hyper-threading aware, and so the OS will only use the second architectural state on a physical processor core when there are more active threaded than there are physical cores on the system. If you check your system’s performance using the windows performance monitoring tool, you will see that your system sees each physical core as two logical cores. For example, the Intel i9 10900K has 10 physical processor cores and shows up on windows as having 10 cores and 20 threads. That said, even though enabling hyper-threading doubles the number of logical processors available to the system, this does not mean that you’re going to see double the performance. This is so because each logical processor must share microarchitecture components with the other logical processors, and so the system’s performance is not doubled. In fact, intel claims that enabling hyper-threading only increases a single socket’s system performance by up to 30%, which is a modest performance boost. 

Frequently Asked Questions (FAQs) 

  1. When was Intel Hyperthreading first used?

Intel hyper-threading was first used on desktop CPUs with the introduction of the Intel Pentium 4 in 2002. When the Intel Pentium 4 was introduced, it had a single hyper-threaded core that appeared as two logical cores to the operating system.  

  1. Are threads as good as cores?

No, threads are not as good as cores because threads utilize the same resources; having more cores is always better than having more threads because each CPU core is like having a separate processor with its own resources. 

  1. Do all i7 processors have hyper-threading?

No, not all i7 processors have hyperthreading. For example, the Intel i7-9700K processor does not have hyperthreading. It has 8 cores and 8 threads, with each core featuring a single thread. 

  1. Why does hyper-threading increase performance?

Hyperthreading increases performance because it allows the CPU to use resources more efficiently by allowing multiple threads to run on each physical core. This increases your processor’s throughput, thereby boosting the overall performance of the software you’re running.  

  1. Does AMD have a technology similar to Intel’s hyper-threading?

Yes, AMD has a similar technology that it refers to as simultaneous multithreading. AMD’s technology also enables better distribution and handling of multiple tasks through their multithreading.