Do not emulate Win11,Linux not only continue to support AMD Zen 2, but also optimize its performance

CTOnews.com June 3, according to foreign technology media NeoWin reports, Linux distribution will not follow Win11, not only continue to provide support for Zen 2-based AMD Ryzen processors, but also further improve performance by optimizing L3 cache (LLC).

The operating system assigns tasks to processor threads marked as "idle", but the current Linux kernel only recognizes idle threads in the local L3 cache; the recently released select_idle_sibling () patch considers calling external LLC.

CTOnews.com attached two pictures to show the structure diagram of AMD Zen 2 CCX and CCD. You can see the difference between the cache structure of single CCD and double CCD:

Single CCD

Dual CCDRed Hat developer Tejun Heo said that on Zen 2 devices, the Linux system has a total of three cores / LLC and a total of four LLC when processing queues for work on a particular LLC, and most cores are idle.

This is mainly because select_idle_sibling () does not consider anything other than the local LLC, and because all these tasks run in a short period of time, the periodic idle load balancer is invalid.

While it's good to keep the working cache locally, it's best not to have a lot of free time. Therefore, when the local node is idle, let select_idle_sibling () try another LLC within the same node.