Struct CpuLimits 

#[non_exhaustive]
pub struct CpuLimits {
    pub max_quota_us: Option<u64>,
    pub max_period_us: u64,
    pub weight: Option<u32>,
}

CPU controller limits (cpu.max + cpu.weight) for a cgroup. All fields default to “inherit from parent” — the framework only writes each knob when its corresponding field is Some.

Set via CgroupDef::cpu_quota_pct / CgroupDef::cpu_quota / CgroupDef::cpu_weight (clear a cap with CgroupDef::cpu_unlimited). The kernel allows quota and weight to coexist (per Documentation/admin-guide/cgroup-v2.rst, “CPU Interface Files”): weight biases relative CPU share inside period, quota enforces an absolute ceiling. Surfacing both as independent options lets a test author express “this cgroup gets at most 50% of one CPU AND should lose to a heavier sibling under contention” in a single declaration.

Validation runs at apply_setup time — any violation surfaces as anyhow::bail! so a misconfigured CgroupDef fails before any worker spawns.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

max_quota_us: Option<u64>

cpu.max quota and period in microseconds. quota = None means “max” (no upper bound). quota = Some(q) allows the cgroup q µs of CPU time per period. q > period is legal: it lets the cgroup use multiple CPUs concurrently (e.g. quota 200_000 / period 100_000 = up to 2 CPUs of throughput).

period defaults to 100_000 µs (100 ms) when omitted via the CgroupDef::cpu_quota_pct convenience builder. Set via CgroupDef::cpu_quota when a non-default period is needed (e.g. tighter control loops with 10 ms periods for latency-sensitive scheduler tests).

max_period_us: u64

cpu.max period component. Required whenever max_quota_us is Some; ignored when max_quota_us is None (the framework writes "max <period>" so the period stays recorded for diagnostics).

weight: Option<u32>

cpu.weight relative-share weight (range 1..=10000, default 100). None leaves the kernel default in place. Larger values get a larger share when the parent cgroup’s CPU is contended.

Trait Implementations

impl Clone for CpuLimits

fn clone(&self) -> CpuLimits

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CpuLimits

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

Formats the value using the given formatter.

impl Default for CpuLimits

fn default() -> Self

cpu.max quota off, period 100 ms (the kernel default for cpu.max’s second column), cpu.weight unset. Matches the initial state used by the four CgroupDef::cpu_* builders; changing the default period only edits here.

The derived Default would produce max_period_us: 0 which apply_setup rejects (kernel requires period > 0). Manual impl avoids that footgun for ..Default::default() callers.

impl PartialEq for CpuLimits

fn eq(&self, other: &CpuLimits) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for CpuLimits

impl StructuralPartialEq for CpuLimits