Struct Curve 

pub struct Curve { /* private fields */ }

An arrival curve (also commonly called an “upper event arrival curve” η+) that can describe arbitrarily bursty sporadic arrival processes.

As is common, the arrival curve is defined by a finite delta-min vector that describes the minimum interval length in which a certain number of jobs may arrive.

Implementations

impl Curve

pub fn new(delta_min_prefix: Vec<Duration>) -> Curve

Construct a new arrival curve.

The delta_min_prefix is the delta-min prefix describing the arrival curve. Each element of the vector gives the minimum interval length in which a corresponding number of jobs may arrive. Convention: we do not store the mininum distance for 0 and 1 jobs. So the min_distance vector at offset 0 contains the minimum separation of two jobs, the min_distance vector at offset 1 contains the length of the shortest interval in which three jobs arrive, and so on.

pub fn from_arrival_bound_until<T: ArrivalBound>( ab: &T, horizon: Duration, ) -> Curve

Obtain an arrival curve by inferring a delta-min vector from any given arrival process T.

The delta-min vector is chosen such that it covers all arrivals until the given horizon.

pub fn from_arrival_bound<T: ArrivalBound>(ab: &T, up_to_njobs: usize) -> Curve

Obtain an arrival curve by inferring a delta-min vector from any given arrival process T.

The delta-min vector is chosen such that it covers at least up_to_njobs job arrivals.

pub fn from_trace( arrival_times: impl Iterator<Item = Offset>, prefix_jobs: usize, ) -> Curve

Obtain an arrival curve by inferring a delta-min prefix from a given trace of arrival events, expressed as the offset of the event from a reference time zero.

The resultant delta-min vector will consist of prefix_jobs entries (if there are a sufficient number of arrivals in the trace).

pub fn extrapolate(&mut self, horizon: Duration)

Extend the underlying delta-min prefix by exploiting the subadditivity of proper arrival curves until the delta-min prefix covers intervals of length horizon.

pub fn extrapolate_steps(&mut self, n: usize)

Extend the underlying delta-min prefix by exploiting the subadditivity of proper arrival curves by n elements.

pub fn extrapolate_with_bound(&mut self, bound: (Duration, usize))

Extend the underlying delta-min prefix by one element while exploiting both the subadditivity of proper arrival curves and the provided bound on the next step. The bound is a tuple (delta, njobs), where njobs must be the element that the underlying delta-min vector is extrapolated to.

pub fn min_distance(&self, n: usize) -> Duration

Return a lower bound on the length of an interval in which n arrival events occur.

Note: does not extrapolate, so extremely pessimistic if n exceeds the length of the internal minimum-distance prefix.

Trait Implementations

impl ArrivalBound for Curve

fn number_arrivals(&self, delta: Duration) -> usize

Bound the number of jobs released in any interval of length delta.

fn steps_iter<'a>(&'a self) -> Box<dyn Iterator<Item = Duration> + 'a>

Yield the sequence of interval lengths (i.e., values of delta in ArrivalBound::number_arrivals) for which the arrival bound “steps”, i.e., where it shows an increase in the number of released jobs.

fn clone_with_jitter(&self, jitter: Duration) -> Box<dyn ArrivalBound>

Clone the arrival model while accounting for added release jitter. Returns a boxed dyn object because the underlying type may change.

fn brute_force_steps_iter<'a>( &'a self, ) -> Box<dyn Iterator<Item = Duration> + 'a>

Same semantics as ArrivalBound::steps_iter, but provided by a default implementation in the most naive way possible. Avoid if performance is at all important.

impl Clone for Curve

fn clone(&self) -> Curve

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Curve

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

Formats the value using the given formatter.

impl From<&ArrivalCurvePrefix> for Curve

fn from(ac: &ArrivalCurvePrefix) -> Self

Converts to this type from the input type.

impl From<ArrivalCurvePrefix> for Curve

fn from(ac: ArrivalCurvePrefix) -> Self

Converts to this type from the input type.

impl From<Periodic> for Curve

fn from(p: Periodic) -> Self

Converts to this type from the input type.

impl From<Sporadic> for Curve

fn from(s: Sporadic) -> Self

Converts to this type from the input type.

impl FromIterator<Duration> for Curve

fn from_iter<I: IntoIterator<Item = Duration>>(iter: I) -> Curve

Creates a value from an iterator.