Enum BackendChange 

pub enum BackendChange {
    StreamsStarted(usize),
    StreamsEnded(usize),
    ConnectionClosed,
    DialFailed(Instant),
}

The accounting operations BackendDelta can carry.

The two counters invariant 14 is about, plus the release of a reservation whose dial never started. The other health and latency writes the mux makes (failures and retry_policy on an asynchronous connect failure, connection_time) are NOT here: they stay immediate at their existing embedder-side call sites rather than being deferred to a drain.

Variants

StreamsStarted(usize)

Backend::active_requests += n — n streams started on this backend.

StreamsEnded(usize)

Backend::active_requests -= n, saturating — n streams left it.

ConnectionClosed

Backend::dec_connections() — the connection to this backend closed, or a dial that connected was abandoned before its connection was registered (Mux::dial_backend, #1713): either way the reservation selection took is released, and no failure is recorded.

DialFailed(Instant)

The connect(2) of a dial failed at this instant (#1684): release the reservation selection took (Backend::dec_connections()), and record the failure (failures += 1, retry_policy.fail), as Backend::release_failed_dial does. The drain before the next selection applies it, so that selection sees the backend exactly as a failed Backend::try_connect left it.

Trait Implementations

impl Clone for BackendChange

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for BackendChange

impl Debug for BackendChange

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

Formats the value using the given formatter.

impl Eq for BackendChange

impl PartialEq for BackendChange

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for BackendChange