Struct ConnectTiming 

pub struct ConnectTiming {
    pub dns: Duration,
    pub tcp: Duration,
    pub tls: Option<Duration>,
    pub total: Duration,
}

What each phase of a connect cost.

The three phases are three measurements, not a decomposition. dns + tcp + tls <= total always holds — they are disjoint intervals inside the whole — but the remainder is real time belonging to none of them: RFC 8305 staggers connection attempts, so a winner that started 250 ms into the race spent that stagger in no phase at all, and a first attempt made through an HTTPS record’s hints and failed is time the second attempt’s phases do not contain either.

Every duration is measured on the transport’s own Timer — the same clock its timeouts and its pool deadlines use, so a test under tokio::time::pause() sees one consistent story rather than two.

Fields

dns: Duration

From the start of the connect to the moment the first address could be tried.

A DNS figure in the honest sense — everything waited for is a DNS answer — but not only an A/AAAA one: an HTTPS record (RFC 9460) is looked up beside the addresses and its hints are tried first, so a slow record delays the first attempt and shows up here.

tcp: Duration

The winning TCP attempt, from the moment it was launched to the moment it connected. Not the race: an attempt the scheduler started earlier and that lost is not in this number.

tls: Option<Duration>

The TLS handshake, or None for a connection that has none — which is the honest answer for http://, where a zero would read as an instant handshake.

total: Duration

The whole connect, from the transport asking for a connection to having one: DNS, every attempt including those that failed, and TLS.

Trait Implementations

impl Clone for ConnectTiming

fn clone(&self) -> ConnectTiming

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ConnectTiming

impl Debug for ConnectTiming

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

Formats the value using the given formatter.

impl Eq for ConnectTiming

impl PartialEq for ConnectTiming

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ConnectTiming