Intel website confirms core configurations of upcoming Alder Lake processors
Intel has published developer guides for its upcoming Alder Lake processors. In it, the chipmaker confirms the different core numbers for laptop and desktop models. The first Alder Lake CPUs are expected to be released on November 4.
Intel reports on its website that several variants for desktop and mobile applications will be released, which will be available with different combinations of CPU cores and GPU execution units. The company reports that Alder Lake-P CPUs for laptops will have up to six powerful P-cores and eight energy-efficient E-cores. The same was previously apparent from a leaked roadmap, but has now been officially confirmed. Intel also writes that all Alder Lake SKUs for laptops come with E-cores. The laptop models also get integrated GPUs with up to 96 execution units.
The chipmaker also writes that Alder Lake-S desktop processors get a maximum of eight P-cores and eight E-cores. Desktop models without E-cores will also appear. That is in line with previous expectations; recently an Intel Core i5-12400 with only six P-cores surfaced. The desktop SKUs with integrated GPUs will also receive 32 execution units, Intel writes.
Image via Intel
Core types and instruction sets
The company also publishes details about the different cores used in the Alder Lake chips. As the company previously confirmed, Alder Lake will be covered under P-cores, codenamed Golden Cove. Those cores are performance-oriented and support hyperthreading. At the same time, the chips are getting E-cores, which the company calls Gracemont. They are focused on efficiency and do not offer hyperthreading.
Both core types have their own pools of L1 and L2 cache, so they can work largely independently of each other. The L3 cache is shared. According to Intel, the cores also support the same instruction sets. The manufacturer states that only the P-cores support AVX-512, and that those instructions can only be executed when the E-cores are disabled in the bios. Ian Cutress of Anandtech poses on Twitter however, that this is a bug, and that AVX-512 is not supported at all on Alder Lake. “The guide is being updated. It has been confirmed that AVX-512 is not in Alder Lake,” he writes.
Images via Intel
Software Optimizations for Alder Lake
Intel further focuses on software optimizations for this hybrid architecture in the developer guide. The processors use an Intel Thread Director. This should make the OS used aware of the different performance and efficiency of the two types of cores. This allows the Thread Director to divide different calculation tasks between the correct core types. Without this director, an OS would think that all cores are equally fast, and tasks could be distributed among the wrong cores.
The company shares various ‘optimization strategies’ for developers of applications and games. Applications that are not optimized in any way for Alder Lake can still use the two core types thanks to the aforementioned Intel Thread Director, which attempts to automatically distribute workloads between the cores. That should ensure better performance “in most cases”, but Intel writes that in certain cases it can prevent some tasks from running on the wrong core type.
In a ‘good’ scenario, in which the developer has taken ‘minimal steps’ to create hybrid awareness, the primary tasks would be divided among the P-cores. Non-essential background tasks should be focused on the E-cores.
In the ‘best’ scenario, developers would create a task system with two thread pools. A primary pool would focus on compute heavy tasks intended for P-cores. The secondary thread pool should perform tasks that are ‘good for E-cores’. Intel mentions several examples, such as audio mixing, shader compilation, asset streaming, and decompression. Developers could also offload primary tasks to E-cores when the performance cores are overloaded and there is capacity left on the efficient cores.
The company further confirms that it is working with middleware companies to add support for the Alder Lake platform and its “hybrid architecture” to engines such as Unreal Engine and Unity. That should happen in ‘future releases’. The company also works with companies like Denuvo to ensure that certain DRM software can recognize the Alder Lake architecture.
First chips appear this quarter
Intel again confirms that the Alder Lake platform will be introduced worldwide in the fourth quarter of this year, although the chipmaker itself does not mention concrete data yet. Intel is expected to release the first Alder Lake models on November 4, according to leaked information from MSI. This would involve overclockable K and KF processors for desktops, with the latter models not having an integrated GPU. The first laptop chips and lower-ranked desktop models are expected later.