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LfudaMeta

Struct LfudaMeta 

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

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::lfuda::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§

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impl LfudaMeta

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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
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pub fn increment(&mut self) -> u64

Increments the frequency counter and returns the new value.

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pub fn priority(&self) -> u64

Calculates the effective priority (frequency + age_at_insertion).

Trait Implementations§

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impl Clone for LfudaMeta

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fn clone(&self) -> LfudaMeta

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
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impl Copy for LfudaMeta

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impl Debug for LfudaMeta

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

Formats the value using the given formatter. Read more
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impl Default for LfudaMeta

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fn default() -> LfudaMeta

Returns the “default value” for a type. Read more
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impl Eq for LfudaMeta

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impl PartialEq for LfudaMeta

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

Equality operator ==. Read more
1.0.0 (const: unstable) · Source§

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

Inequality operator !=. Read more
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impl StructuralPartialEq for LfudaMeta

Auto Trait Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

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fn equivalent(&self, key: &K) -> bool

Compare self to key and return true if they are equal.
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = !

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, !>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.