Struct L2Domain 

pub struct L2Domain {
    pub size_bytes: u64,
    pub mask: AffinityMask,
    pub core_count: u16,
    pub l3_domain: u8,
}

A set of cores sharing one L2 cache instance.

Where an L3Domain is the last-level-cache sharing group (a CCD on chiplet AMD, a cluster on hybrid Intel), an L2 domain is the much finer group that shares one L2: on most desktop parts that is a single physical core plus its SMT siblings; on hybrid Intel the efficiency cores share an L2 in clusters. Sharing L2 is the shortest core-to-core path, so this is the granularity at which two threads are “closest” - the unit for slicing a few cooperating threads out of a larger L3 domain.

Domains are content-keyed during detection (by the lowest member LP of the cache’s shared set), and each carries its own size_bytes, so heterogeneous L2 sizes (mixed core kinds) are represented exactly rather than collapsed to a per-kind average.

Fields

size_bytes: u64

Size of this L2 instance in bytes.

mask: AffinityMask

The LPs (OS ids) sharing this L2 instance.

core_count: u16

Physical cores in this domain (SMT siblings counted once).

l3_domain: u8

Index of the parent L3Domain these cores share, or Lp::NO_L3 when the machine reports no L3 (e.g. Apple Silicon). Every LP in an L2 domain shares one L3, so this lets a caller walk the L2 groups inside a single L3 domain without intersecting masks.

Trait Implementations

impl Clone for L2Domain

fn clone(&self) -> L2Domain

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for L2Domain

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.