Struct KvCachePolicy 

pub struct KvCachePolicy { /* private fields */ }

Stateful KV-cache compression policy.

Thread-safe: the current level is stored in an AtomicU8 so concurrent observers can read without locking. The pressure EWMA is also stored atomically (as u64-encoded f64 bits).

Implementations

impl KvCachePolicy

pub fn new(config: KvCachePolicyConfig) -> Result<Self, KvCachePolicyError>

Construct a new policy.

Returns an error if the config is invalid (out-of-range thresholds, inverted hysteresis, or min_level > max_level).

pub fn current_level(&self) -> KvCacheLevel

Read the current level.

pub fn pressure(&self) -> f64

Read the smoothed pressure (EWMA).

pub fn samples(&self) -> u64

Number of observations recorded so far.

pub fn upgrades(&self) -> u64

Number of upgrades fired since construction.

pub fn downgrades(&self) -> u64

Number of downgrades fired since construction.

pub fn observe(&self, pressure: f64) -> KvCacheLevel

Record a new pressure observation and return the (possibly updated) active level.

pressure is expected in [0.0, 1.0]; values are clamped to that range before being fed into the EWMA.

pub fn reset(&self)

Reset the EWMA, sample counter, and tier to the configured minimum. Counters for upgrades/downgrades are also reset.

pub fn config(&self) -> &KvCachePolicyConfig

Return the configuration this policy was built with.

Trait Implementations

impl Debug for KvCachePolicy

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

Formats the value using the given formatter.

impl Default for KvCachePolicy

fn default() -> Self

Returns the “default value” for a type.