Struct InstanceStats 

pub struct InstanceStats {
    pub ops_observed: u64,
    pub total_latency_ticks: u64,
    pub contention_ops: u64,
    pub op_kind_counts: [u64; 8],
    pub last_seen_us_ago: u64,
    pub migrations_triggered: u64,
    pub per_op_kind_distinct_threads: [[u32; 4]; 8],
    pub per_op_kind_distinct_count: [u8; 8],
}

Aggregated statistics for one registered instance.

Updated by the sidecar each poll cycle from drained observations.

Fields

ops_observed: u64

total_latency_ticks: u64

contention_ops: u64

op_kind_counts: [u64; 8]

Per-op-kind counts. Index by Observation.op_kind (clamped to the valid range). Primitives that adapt based on a ratio of op kinds (e.g., reads vs writes) consume these.

last_seen_us_ago: u64

migrations_triggered: u64

Number of migrations the sidecar has triggered on this instance (apply_migration calls that resulted in a tag change). Used by bench harnesses to measure adaptation-latency convergence.

per_op_kind_distinct_threads: [[u32; 4]; 8]

Per-op-kind distinct-thread-id cache. Filled lazily by the drain as observations arrive. Once a slot fills with a tid that doesn’t match any earlier slot, the corresponding count in per_op_kind_distinct_count increments.

per_op_kind_distinct_count: [u8; 8]

Distinct thread count observed per op_kind (saturates at MAX_TRACKED_THREADS_PER_KIND + 1 - meaning “more than the slot table can hold”). >= 2 is the typical multi-producer or multi-consumer detection threshold for primitive policies.

Implementations

impl InstanceStats

pub fn average_latency_ticks(&self) -> u64

pub fn contention_rate(&self) -> f64

pub fn op_kind_total(&self) -> u64

Total ops observed across all op kinds. Equals ops_observed for primitives that always set a non-zero op_kind on their observations.

pub fn ratio_of(&self, kind: u16, total_kinds: &[u16]) -> f64

Ratio of one op kind to the total of two op kinds. Returns 0.0 when both counts are zero (avoids divide-by-zero in policies).

pub fn distinct_threads_for(&self, kind: u16) -> u8

Distinct producer-thread count observed for one op kind.

>= 2 indicates true multi-producer (or multi-consumer for the recv-side op kind) usage on this primitive - the right signal for a ChannelPolicy promoting SPSC → MPMC, an AdaptiveCell noticing multi-writer churn, etc. Saturates at MAX_TRACKED_THREADS_PER_KIND + 1.

pub fn is_multi_thread_for(&self, kind: u16) -> bool

True when the given op kind has been observed from more than one distinct producer thread.

Trait Implementations

impl Clone for InstanceStats

fn clone(&self) -> InstanceStats

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for InstanceStats

impl Debug for InstanceStats

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

Formats the value using the given formatter.

impl Default for InstanceStats

fn default() -> Self

Returns the “default value” for a type.