Struct mz_storage::upsert::memory::InMemoryHashMap

pub struct InMemoryHashMap<T, O> {
    state: HashMap<UpsertKey, StateValue<T, O>>,
    total_size: i64,
}

A HashMap tracking its total size

Fields

state: HashMap<UpsertKey, StateValue<T, O>>

total_size: i64

Implementations

impl<T, O> InMemoryHashMap<T, O>

pub fn drain(&mut self) -> (i64, Drain<'_, UpsertKey, StateValue<T, O>>)

Drain the map, returning the last total size as well.

pub fn current_size(&self) -> i64

Get the current size of the map. Note that after drain-ing, this is 0.

Trait Implementations

impl<T, O> Default for InMemoryHashMap<T, O>

fn default() -> Self

Returns the “default value” for a type.

impl<T, O> UpsertStateBackend<T, O> for InMemoryHashMap<T, O>

where O: Clone + 'static, T: Clone + 'static,

fn supports_merge(&self) -> bool

Whether this backend supports the multi_merge operation.

fn multi_put<'life0, 'async_trait, P>( &'life0 mut self, puts: P, ) -> Pin<Box<dyn Future<Output = Result<PutStats, Error>> + 'async_trait>>

where P: IntoIterator<Item = (UpsertKey, PutValue<StateValue<T, O>>)> + 'async_trait, Self: 'async_trait, 'life0: 'async_trait,

Insert or delete for all puts keys, prioritizing the last value for repeated keys.

fn multi_merge<'life0, 'async_trait, M>( &'life0 mut self, _merges: M, ) -> Pin<Box<dyn Future<Output = Result<MergeStats, Error>> + 'async_trait>>

where M: IntoIterator<Item = (UpsertKey, MergeValue<StateValue<T, O>>)> + 'async_trait, Self: 'async_trait, 'life0: 'async_trait,

For each key in merges writes a ‘merge operand’ to the backend. The backend stores these merge operands and periodically calls the consolidating_merge_function to merge them into any existing value for each key. The backend will merge the merge operands in the order they are provided, and the merge function will always be run for a given key when a get operation is performed on that key, or when the backend decides to run the merge based on its own internal logic. This allows avoiding the read-modify-write method of updating many values to improve performance.

fn multi_get<'r, 'life0, 'async_trait, G, R>( &'life0 mut self, gets: G, results_out: R, ) -> Pin<Box<dyn Future<Output = Result<GetStats, Error>> + 'async_trait>>

where G: IntoIterator<Item = UpsertKey> + 'async_trait, R: IntoIterator<Item = &'r mut UpsertValueAndSize<T, O>> + 'async_trait, Self: 'async_trait, 'r: 'async_trait, 'life0: 'async_trait,

Get the gets keys, which must be unique, placing the results in results_out.