Struct AckFrequency 

#[non_exhaustive]
pub struct AckFrequency {
    pub ack_eliciting_threshold: u64,
    pub max_ack_delay: Option<Duration>,
    pub reordering_threshold: u64,
}

Acknowledgement frequency to request of the peer.

A serializable mirror of quinn’s AckFrequencyConfig, which has private fields, no getters and no serde support, so it cannot itself appear in a profile. The three fields are the three knobs that type exposes, and the Default is hand-written to equal quinn’s own defaults rather than derived: a derived one would give an ack-eliciting threshold of zero, which asks the peer to acknowledge every single packet, and a reordering threshold of zero, which asks it never to acknowledge reordering promptly. Neither is a sensible starting point, and both would arrive silently in any file that named one field and left the others out.

With this Default, Some(AckFrequency::default()) means exactly what Some(AckFrequencyConfig::default()) means in quinn: negotiate the extension, with its recommended values.

#[non_exhaustive], so outside this crate one is built as AckFrequency::default() followed by field assignment — the attribute makes both the struct expression and ..Default::default() illegal there. Kept rather than dropped because it and the Default above are one mechanism: this type mirrors an upstream config that gains a knob from time to time, and the attribute guarantees that every construction still reachable starts from the hand-written Default. A fourth field added in a later release therefore arrives carrying quinn’s recommended value in code that was written before it existed, instead of the zero a struct expression would have left there — and zero, for both thresholds here, is a request the peer will honour and nobody meant to make.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

ack_eliciting_threshold: u64

How many ack-eliciting packets the peer may receive before it must send an acknowledgement.

Zero asks it to acknowledge every one. Defaults to 1, which is quinn’s own default and acknowledges every other packet.

max_ack_delay: Option<Duration>

The longest the peer may wait before acknowledging, when the threshold above has not been reached.

None leaves the peer’s own advertised max_ack_delay in place, which is quinn’s default and is why None is not ambiguous here.

reordering_threshold: u64

How far out of order a packet may arrive before the peer must acknowledge immediately.

Zero asks it never to. Defaults to 2, which is quinn’s own default and one below the default packet threshold, as quinn recommends.

Implementations

impl AckFrequency

fn validate(&self) -> Result<(), TransportProfileError>

The two varint-valued thresholds, checked against the QUIC varint ceiling before they can fail at connect time.

Field names are reported dotted — ack_frequency.reordering_threshold — because reordering_threshold on its own would not tell a reader which part of the file to look at.

fn to_config(&self) -> Result<AckFrequencyConfig, TransportProfileError>

Build quinn’s config from this mirror.

Trait Implementations

impl Clone for AckFrequency

fn clone(&self) -> AckFrequency

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AckFrequency

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

Formats the value using the given formatter.

impl Default for AckFrequency

fn default() -> Self

Returns the “default value” for a type.

impl Eq for AckFrequency

impl PartialEq for AckFrequency

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for AckFrequency