Struct Backoff 

pub struct Backoff { /* private fields */ }

Performs exponential backoff in spin loops.

Backing off in spin loops reduces contention and improves overall performance.

This primitive can execute YIELD and PAUSE instructions, yield the current thread to the OS scheduler, and tell when it is a good time to block the thread using a different synchronization mechanism. Each step of the back off procedure takes roughly twice as long as the previous step.

Implementations

impl Backoff

pub fn new() -> Self

Creates a new Backoff instance.

pub fn step(&self) -> u32

Returns the current backoff step (how many times it has been called since the last reset).

pub fn reset(&self)

Resets the backoff state.

pub fn spin(&self)

Backs off in a lock-free loop.

This method should be used when we need to retry an operation because another thread made progress.

The processor may yield using the YIELD or PAUSE instruction.

pub fn spin_or<F>(&self, f: F)

where F: FnOnce(),

It spins or calls the provided function if it should be used.

If the provided function is std::thread::yield_now, then this function has the same behaviour as snooze.

pub fn snooze(&self)

Backs off in a blocking loop.

This method should be used when we need to wait for another thread to make progress.

The processor may yield using the YIELD or PAUSE instruction, and the current thread may yield by giving up a timeslice to the OS scheduler.

In #[no_std] environments, this method is equivalent to spin.

If possible, use is_completed to check when it is advised to stop using backoff and block the current thread using a different synchronization mechanism instead.

pub fn is_completed(&self) -> bool

Returns true if exponential backoff has completed and blocking the thread is advised.

Trait Implementations

impl Debug for Backoff

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

Formats the value using the given formatter.

impl Default for Backoff

fn default() -> Self

Returns the “default value” for a type.