Struct LfudaMeta 

pub struct LfudaMeta {
    pub frequency: u64,
    pub age_at_insertion: u64,
}

Metadata for LFUDA (LFU with Dynamic Aging) cache entries.

LFUDA is similar to LFU but addresses the “aging problem” where old frequently-used items can prevent new items from being cached. The age factor is maintained at the cache level, not per-entry.

Algorithm

Entry priority = frequency + age_at_insertion

• When an item is evicted, global_age = evicted_item.priority
• New items start with current global_age as their insertion age

Examples

use cache_rs::meta::LfudaMeta;

let meta = LfudaMeta::new(1, 10); // frequency=1, age_at_insertion=10
assert_eq!(meta.frequency, 1);
assert_eq!(meta.age_at_insertion, 10);
assert_eq!(meta.priority(), 11);

Fields

frequency: u64

Access frequency count.

age_at_insertion: u64

Age value when this item was inserted (snapshot of global_age).

Implementations

impl LfudaMeta

pub fn new(frequency: u64, age_at_insertion: u64) -> Self

Creates a new LFUDA metadata with the specified initial frequency and age.

Arguments

• frequency - Initial frequency value (usually 1 for new items)
• age_at_insertion - The global_age at the time of insertion

pub fn increment(&mut self) -> u64

Increments the frequency counter and returns the new value.

pub fn priority(&self) -> u64

Calculates the effective priority (frequency + age_at_insertion).

Trait Implementations

impl Clone for LfudaMeta

fn clone(&self) -> LfudaMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LfudaMeta

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

Formats the value using the given formatter.

impl Default for LfudaMeta

fn default() -> LfudaMeta

Returns the “default value” for a type.

impl PartialEq for LfudaMeta

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for LfudaMeta

impl Eq for LfudaMeta

impl StructuralPartialEq for LfudaMeta