Struct MergeIterator

pub struct MergeIterator<I: HummockIterator> {
    unused_iters: LinkedList<Node<I>>,
    heap: BinaryHeap<Node<I>>,
}

Iterates on multiple iterators, a.k.a. MergeIterator.

Fields

unused_iters: LinkedList<Node<I>>

Invalid or non-initialized iterators.

heap: BinaryHeap<Node<I>>

The heap for merge sort.

Implementations

impl<I: HummockIterator> MergeIterator<I>

fn collect_local_statistic_impl(&self, stats: &mut StoreLocalStatistic)

impl<I: HummockIterator> MergeIterator<I>

pub fn new(iterators: impl IntoIterator<Item = I>) -> Self

pub fn for_compactor(iterators: impl IntoIterator<Item = I>) -> Self

fn create(iterators: impl IntoIterator<Item = I>) -> Self

impl MergeIterator<SharedBufferBatchIterator<Forward>>

pub(crate) fn current_key_entry(&self) -> SharedBufferVersionedEntryRef<'_>

Used in merge_imms_in_memory to merge immutable memtables.

impl<I: HummockIterator> MergeIterator<I>

where Node<I>: Ord,

fn reset_heap(&mut self)

Moves all iterators from the heap to the linked list.

fn build_heap(&mut self)

After some iterators in unused_iterators are sought or rewound, calls this function to construct a new heap using the valid ones.

impl MergeIterator<SharedBufferBatchIterator<Forward>>

pub(crate) fn advance_peek_to_next_key(&mut self)

pub(crate) fn rewind_no_await(&mut self)

Trait Implementations

impl<I: HummockIterator> HummockIterator for MergeIterator<I>

where Node<I>: Ord,

type Direction = <I as HummockIterator>::Direction

async fn next(&mut self) -> HummockResult<()>

Moves a valid iterator to the next key.

fn key(&self) -> FullKey<&[u8]>

Retrieves the current key.

fn value(&self) -> HummockValue<&[u8]>

Retrieves the current value, decoded as HummockValue.

fn is_valid(&self) -> bool

Indicates whether the iterator can be used.

async fn rewind(&mut self) -> HummockResult<()>

Resets the position of the iterator.

async fn seek<'a>(&'a mut self, key: FullKey<&'a [u8]>) -> HummockResult<()>

Resets iterator and seeks to the first position where the key >= provided key, or key <= provided key if this is a backward iterator.

fn collect_local_statistic(&self, stats: &mut StoreLocalStatistic)

take local statistic info from iterator to report metrics.

fn value_meta(&self) -> ValueMeta

Returns value meta.