[The Exiled]

When you have two cores of different performance and efficiency points, either the processor or the operating system has to be cognizant of what goes where to get the best result from the end-user. Intel Thread Director is a combined hardware/software solution that Intel has engineered with Microsoft focused on Windows 11. It all boils down to having the right functionality to help the operating system make decisions about where to put threads that require low latency vs threads that require high efficiency but are not time critical. First you need a software scheduler that knows what it is doing. Intel’s Thread Director controller puts an embedded microcontroller inside the processor such that it can monitor what each thread is doing and what it needs out of its performance metrics.

It then provides suggested hints back to the Windows 11 OS scheduler about what the thread is doing, whether it is important or not, and it is up to the OS scheduler to combine that with other information about the system as to where that thread should go. Ultimately the OS is both topologically aware and now workload aware to a much higher degree. It’s important to understand that for the desktop processor with 8 P-cores and 8 E-cores, if there was a 16-thread workload then it will be scheduled across all 8 P-cores with 8 threads, then all 8 E-cores with the other 8 threads. Windows 10 does not get Thread Director, but relies on a more basic version of Intel’s Hardware Guided Scheduling (HGS).

In our conversations with Intel, they were cagy to put any exact performance differential metrics between the two, however based on understanding of the technology, we should expect to see better frequency efficiency in Windows 11.

Thread Director is ONLY compatible with Windows 11, Windows 10 does not have the tools to see TD data much less use it. Intel went to great lengths and had painfully tortured logic to say that Windows 10 has a lot of heterogeneous core capabilities without TD. It doesn’t. Heterogeneous cores on Windows serve one purpose, so Intel can catch up with AMD on the core count marketing slides. AMD has been delivering real 16C desktop CPUs for years now, soon Intel will be able to claim the same number, albeit fake, of cores. Yay marketing.

It’s important to understand that for the desktop processor with 8 P-cores and 8 E-cores, if there was a 16-thread workload then it will be scheduled across all 8 P-cores with 8 threads, then all 8 E-cores with the other 8 threads. This affords more performance than enabling the hyperthreads on the P-cores, and so software that compares thread-to-thread loading (such as the latest 3DMark CPU Profile test) may be testing something different compared to processors without E-cores.

It all boils down to having the right functionality to help the operating system make decisions about where to put threads that require low latency vs threads that require high efficiency but are not time critical. So it’s easy enough (now) to tell an operating system that different types of cores exist. Each one can have a respective performance and efficiency rating, and the operating system can migrate threads around as required. However the difference between Windows 10 and Windows 11 is how much information is available to the scheduler about what is running.

Intel classifies the performance levels on Alder Lake in the following order:

• One thread per core on P-cores
• Only thread on E-cores
• SMT threads on P-cores

That means the system will load up one thread per P-core and all the E-cores before moving to the hyperthreads on the P-cores.

On top of this, Intel says that Thread Director can also optimize for frequency.

If a thread is limited in a way other than frequency, it can detect this and reduce frequency, voltage, and power.

Alder Lake je od strane Intela najavljen kao najbolji gaming CPU, tak da po tom pitanju i dalje sve ostaje isto. Visoki taktovi, popraćni visokom potrošnjom i zagrijavanjem.

I naravno, (od strane korisnika) isključivanje manjih jezgri u BIOS-u, tako da se ostatak može dignuti još više.