■ Intel Thread Director, allocated to optimal processor cores

Intel unveiled Intel Thread Director at Intel Architecture Day held last August.

Intel Thread Director essentially allows a new type of hybrid computer chip to assign the right thread or workload to the right type of processor core.

Intel Thread Director can be likened to an athlete's injury.

When a player injures his leg in a soccer game and goes to a hospital where his family doctor and an orthopedic surgeon are present, the hospital reception desk will assign the patient to an orthopedic specialist who is more knowledgeable about sprains, fractures, and ligament injuries, ensuring that the patient receives optimal treatment.

The thread director is similar to a hospital's assignment system in that it determines which software threads are in the Performance Core.We look at all these low-level statistics to figure out which threads are better suited for Efficient Cores and which ones can get the most benefit from Efficient Cores.

Intel's latest hybrid architecture includes efficient cores and performance cores.

Intel's latest system-on-a-chip (SoC) for PCs, Alder Lake, will be the first computer chip to use a combination of these two types of cores plus Intel's Thread Director.

For a traditional OS with 16 cores running 16 threads, you don't know which core the threads are focused on, and this is where a thread director can come into play.

It also provides the ability to create optimized scheduling recommendations. And it's not about making these decisions at the software layer, it's about tracking nanosecond-by-nanometer runtime telemetry from the hardware and helping the software make the right decisions.

■ Cooperation between hardware and software is essential

When I joined Intel 20 years ago after receiving my master's degree in computer science from Syracuse, I was interested in optimizing customer software.

My team in the Intel Client Computing Group works with software partners to identify common performance, power, and user experience bottlenecks and provide a different perspective on future cores and platforms.

In 2019, the Intel OS software team and I traveled to Israel with the Alder Lake hardware architecture team to validate the Thread Director.

Our team works to address immediate issues through targeted software optimizations, but we also work with hardware teams and designers to feed software analysis results back into future hardware design considerations.

When my software team and I were working with the hardware team in Israel, we knew that we needed an OS based on new performance cores and efficiency cores that could handle a wide range of common client activities like gaming, streaming, content creation, and productivity.

This widespread usage highlights the need for a new hybrid approach.

While many of the most demanding applications run well on one or a few cores, an emerging set of applications will use as many cores as possible. Hybrid processors like Alder Lake provide an answer to both of these problems.

They also wanted software developers to eliminate the overhead of handling scheduling tasks in software without having to reuse existing code, and they quickly realized that only a hardware solution could meet all of these requirements.

This is where Intel Thread Director came into being.

■ Support for more intelligent decision-making by the OS

The chip can monitor the instruction mix, current state of each core, and related microarchitectural telemetry at a granular level to provide smarter support for the OS.

It supports the OS to leverage information and visibility into scheduling decisions that it previously did not have.

The OS would traditionally make decisions based on the limited information available when the number of foreground threads exceeds the number of performance cores.

The thread director adds a new dimension with hardware telemetry to ensure that threads that can benefit most from performance cores are allocated first.

■ Intel maintains balance between performance and power with hybrid design

Hybrid vehicles on the market use hybrid technology to maximize fuel efficiency.

The traditional concept of hybrid computing aims to use a computer for as long as possible on battery power alone without charging.

Formula One cars use hybrid technology to maximize performance.

The car's turbocharged engine provides enough fuel economy and top speed to complete the race on limited fuel.
/> In addition, based on the power of the hybrid engine, it provides acceleration that is impossible with a conventional engine, helping you get out of corners easily.

Formula One cars don't compromise performance for efficiency. Intel balances performance and power with hybrid designs.