Struct Stats 

#[non_exhaustive]
pub struct Stats {

    pub checks: u64,
    pub reports: u64,
    pub units: u64,
    pub overflowed: bool,
    pub max_check_gap: Duration,
    pub max_check_gap_start: Duration,
    pub max_report_gap: Option<ReportGap>,
    pub unit_pace: Option<UnitPace>,
    pub check_time: Duration,
    pub stopped_at: Option<Duration>,
    pub stop_reason: Option<StopReason>,
    pub clock_regressions: u64,
    pub sites: Vec<SiteStats>,
    pub unattributed_calls: u64,
}

One span’s checkpoint evidence. Gaps include entry and exit, so a span with no checks still records how long it ran unchecked.

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.

checks: u64

Cancellation checks (saturating).

reports: u64

Report calls (saturating).

units: u64

Units reported (saturating).

overflowed: bool

Whether any count saturated; rates then lose their meaning.

max_check_gap: Duration

Longest interval without a check: entry to first check, check to check, or last check to exit.

max_check_gap_start: Duration

Start of that interval, in the clock’s epoch.

max_report_gap: Option<ReportGap>

Longest interval between reports, if report timing was on.

unit_pace: Option<UnitPace>

How long each quarter of the reported units took, if report timing was on.

check_time: Duration

Time spent inside instrumented checks, including any work they ran.

Timing a check takes a second clock read, so a span times its first 16 checks, every 16th after them, and every check that returned a stop, and scales the timed total to all its checks. A slow check that was not timed still shows in max_check_gap, which runs from one check’s start to the next.

stopped_at: Option<Duration>

When the first check that returned a stop error finished.

stop_reason: Option<StopReason>

That check’s reason, which keeps cancellation apart from a timeout.

clock_regressions: u64

Times the clock went backwards within one call, or at finish. Workers sharing a span can deliver readings out of order; that is expected, counts as a zero gap, and is not a regression.

sites: Vec<SiteStats>

Up to 64 distinct call sites.

unattributed_calls: u64

Calls from sites beyond the first 64. The totals above still count them.

Trait Implementations

impl Clone for Stats

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Stats

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

Formats the value using the given formatter.

impl Default for Stats

fn default() -> Self

Returns the “default value” for a type.