Struct Sequencer

pub struct Sequencer {
    local: Sequence,
    target: Sequence,
    step: Sequence,
    lag: Sequence,
}

An globally unique and approximate ascending sequence generator with local optimization.

Sequencer can be used to generate globally unique sequence (id) in an approximate order. Sequencer allow the generated sequence to be disordered in a certain window. The larger the allowed disordered sequence window is, the better multithreading performance of the generator will be.

The window is controlled with two arguments, step and lag. step controls the size of the batch of the sequences to allocate by the local sequence generator. lag controls the maximum lag between the local generator and the global generator to avoid skew.

Fields

local: Sequence

target: Sequence

step: Sequence

lag: Sequence

Implementations

impl Sequencer

pub const DEFAULT_LAG: Sequence = 2_048u64

pub const DEFAULT_STEP: Sequence = 64u64

pub const fn new(step: Sequence, lag: Sequence) -> Self

Create a new local sequence generator.

pub fn global(&self) -> Sequence

Get the global sequence to allocate.

pub fn local(&self) -> Sequence

Get the local sequence to allocate.

pub fn alloc(&mut self) -> Sequence

Allocate a new sequence. The allocated sequences from the same Sequencer are strictly ascending, the allocated sequences from different Sequencers are approximate ascending.

fn try_alloc(&mut self)

fn alloc_inner(&mut self)