[Hardware] Intel Alder Lake: this is the most revolutionary CPU architecture

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The twelfth generation of Intel Core processors, not to be confused with the architecture number 12 that they launch, is here and that is why we have prepared an exhaustive article on Alder Lake, the most important CPU architecture in the last decade due to the changes they have incorporated into it. What secrets and news do the Intel Core 12 hide?

In the history of processor architecture every so often a new processor appears that is an important paradigm shift, the last we saw was that of AMD's Zen architecture that we have seen evolve in three different generations and on the way to the fourth. As for Intel, the last big change we saw was when they went from the Netburst architecture of the Pentium IV to Conroe in the first Intel Core, and before that and a decade before with the appearance of the Pentium Pro.

So we are not facing a simple renewal of the range of processors, it is not adding a number, but the changes are much more profound and it is that the Alder Lake-S architecture of the Intel Core 12 will become the basis of the Intel CPU for the next five years.

What can we find in the box?
Intel Core 12: a hybrid architecture
Intel Core 12 Cajai9-12900K i5-12600K Cajai5-12600K Front i9-12900K Front Intel Core 12 Back i9-12900K i5-12600K Front i9-12900K i5-12600K Back

If we discount the appearance of Lakefield, for the first time Intel has bet on its main range of processors for the use of two types of core with different performance and consumption to accelerate the tasks of the processor.

The P-Cores are large cores that offer great performance, but in exchange for being less energy efficient.
E-Cores are smaller cores, allowing Intel to fit more in the same space and have lower power consumption.
Depending on the Intel Core 12 model, the number of P-Cores and E-Cores varies, but we must clarify that both work in unison and in a coordinated manner. For the latter they make use of a third level 30 MB last level cache, which not only gives access to the same memory space to both types of cores, but also allows them to work together in the execution of the processes to be executed. .

Intel Core 12 and Amdahl's Law
Intel 12 hybrid heterogeneous architecture
To understand what is intended to be achieved with the design of the Intel Core 12 we must bear in mind that every program is divided into two parts:

A part that runs in series, on a single processor and therefore it will need to be as fast as possible to accelerate its execution, so this part of the programs in the Intel Core 12 is handled by the P-Cores.
The other part that can be run in parallel, so adding more processors will speed up the resolution of the same more than not having a CPU. The E-Cores are in charge of this type of task.
Nor can we forget that on a PC there are more tasks than we see and the correct assignment of them is important, it may be that while you are playing a game the mail application is updating the inbox. Gaming is a foreground process and email management is a background process, so it's best to assign those secondary tasks to a less powerful processor.

P-Cores vs. E-Cores in single wire
P-Cores E-Cores Performance
Starting with the P-Cores, which are the high-performance cores, we find that their L2 cache is local for each processor, while the E-Cores have this level shared between several cores. Keep in mind that the first two cache levels are not shared between both types of cores.

But what interests us is the performance, and at the same clock speed we find that the P-Cores obtain 28% additional performance compared to the tenth generation of Intel Core processors, while the E-Cores are 1% per above with respect to the same generation. So the E-Cores are not cores with a power worthy of a netbook or any very low consumption system, but their single-thread performance is at the height of the Comet Lake.

Although because the E-Cores in Intel Core 12 are designed with a view to energy efficiency, they not only work at a lower clock speed, but also do not have support for HyperThreading.

Performance per Watt, PL1 and PL2
Intel Core 12 PL1 PL2
One way to measure the performance of one processor compared to another is to see how many watts or watts they consume to perform the same task. In the case of the Intel Core 12 we have two consumption profiles, in the so-called PL1 the processor consumption is set at 125 W, while in PL2 it is at 241 W.