Keysight Connect #13 – All about CPU Hyperthreading
Presented by Cosmin Chenaru
Hyperthreading is a technology that enables a single processor to handle multiple tasks simultaneously, thereby improving performance. Intel introduced it in 2002, becoming a standard feature in most of its processors.
In our 13th edition of Keysight Connect dedicated to unlocking the full potential of hyper-threading, we had Cosmin Chenaru walk us through how to better optimize CPUs and what to look after when using Hyper-Threading in High-Performance networking or other Real-Time applications.
Hyperthreading versus Multicore Processing
Although hyperthreading and multicore processing are often mistaken for each other, they are two different technologies. Hyperthreading enables a single core to behave like multiple cores, while multicore processing involves having multiple physical cores on a single processor, each capable of executing a separate thread simultaneously.
The benefits and drawbacks of Hyperthreading
On one hand, the primary benefit of hyperthreading is improved performance. Allowing a single processor to execute multiple threads simultaneously can complete tasks more quickly and efficiently, resulting in better overall system performance. Additionally, hyperthreading can reduce the time a CPU spends idle, as it can switch between threads more rapidly.
On the other hand, a potential drawback is that it can increase power consumption, as the CPU is required to handle multiple threads at the same time. Therefore, some applications may not benefit from hyperthreading and may experience reduced performance.
Hyperthreading and Virtualization
Hyperthreading can also benefit virtualized environments, as virtualization involves running several operating systems or virtual machines (VMs) on a single physical server. Each VM requires its resources, including CPU, memory, and storage, so hyperthreading can allow a single physical core to handle multiple VMs simultaneously, improving overall system performance.
However, hyperthreading may not always be beneficial in virtualized environments because it depends on the specific workload and resources available on the physical server. Some hypervisors may not support hyperthreading or require specific configurations to enable it. Also, from a security point of view, a few security exploits have been reported on machines using Hyperthreading, therefore system admins disable Hyperthreading on hypervisors so that a Virtual Machine will not be able to steal data from another Virtual Machine.
Hyperthreading with Operating Systems and CPUs
When it comes to operating systems, hyperthreading can prove useful in several ways. For example, it can allow multiple applications to run simultaneously without causing the system to slow down. What’s more, it can also improve the performance of multi-threaded applications designed to take advantage of multiple CPU cores. This can lead to faster execution times and improved overall performance.
Regarding CPUs, hyperthreading is particularly useful for CPU-intensive tasks, such as video encoding, scientific simulations, and gaming. These tasks can use multiple logical cores, improving performance and faster completion.
As in the case of virtualization, the advantages of hyperthreading on operating systems and CPUs depend on the specific workload and the resources available on the system, as it may sometimes slow down the system or cause issues with certain applications. As such, it’s important to consider the use of hyperthreading carefully and to monitor system performance to ensure that it remains optimal.
Learn more about hyperthreading by watching the video of our last Keysight Connect meetup 👇