Struct SystemCpuTracker 

pub struct SystemCpuTracker { /* private fields */ }

Aggregate machine CPU utilization from cumulative CPU-time totals (§8.3).

The percentage is busy_delta / (busy_delta + idle_delta). That divisor is CPU time rather than wall time, which makes the result self-normalizing: it is already a share of all logical CPUs, so it lands in 0..=100 without ever being told the CPU count, and a sample interval that drifts from 1 s to 4 s cannot distort it.

The reading Instant is retained even though the percentage does not use it, so that a keyed set of per-core trackers can prune cores that stopped reporting after a CPU hotplug event.

Implementations

impl SystemCpuTracker

pub const fn new() -> Self

Builds a tracker with no baseline.

pub const fn is_warming_up(&self) -> bool

Whether the next reading will be the first, and so warming up (§8.2).

pub const fn last_observed_at(&self) -> Option<Instant>

When the last reading was accepted, or None while warming up.

pub fn forget_baseline(&mut self)

Drops the baseline so the next reading warms up again.

pub fn observe( &mut self, totals: CpuTimeTotals, at: Instant, ) -> MetricState<Percent>

Folds one cumulative CPU-time reading in and publishes machine usage.

Trait Implementations

impl Clone for SystemCpuTracker

fn clone(&self) -> SystemCpuTracker

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SystemCpuTracker

impl Debug for SystemCpuTracker

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

Formats the value using the given formatter.

impl Default for SystemCpuTracker

fn default() -> SystemCpuTracker

Returns the “default value” for a type.

impl DeltaTracker for SystemCpuTracker

type Config = ()

Construction parameters shared by every tracker in one set.

type Reading = CpuTimeTotals

The cumulative reading folded in on each observation.

type Value = Percent

The value published when an observation succeeds.

fn with_config(_config: Self::Config) -> Self

Builds a tracker with no baseline yet.

fn observe_reading( &mut self, reading: Self::Reading, at: Instant, ) -> MetricState<Self::Value>

Folds one cumulative reading in, at monotonic time at.

fn last_observed_at(&self) -> Option<Instant>

When this tracker last accepted a reading, or None while warming up.

fn forget_baseline(&mut self)

Drops the baseline so the next reading warms up instead of producing a delta across a gap (§8.2).