Struct Tree

pub struct Tree(/* private fields */);

A log-structured merge tree (LSM-tree/LSMT)

Trait Implementations

impl AbstractTree for Tree

fn l0_run_count(&self) -> usize

Returns the amount of disjoint runs in L0.

fn size_of<K: AsRef<[u8]>>( &self, key: K, seqno: Option<SeqNo>, ) -> Result<Option<u32>>

Returns the size of a value if it exists.

fn bloom_filter_size(&self) -> usize

Gets the memory usage of all bloom filters in the tree.

fn sealed_memtable_count(&self) -> usize

Returns the amount of sealed memtables.

fn keys( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Box<dyn DoubleEndedIterator<Item = Result<UserKey>> + 'static>

Returns an iterator that scans through the entire tree, returning keys only.

fn values( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Box<dyn DoubleEndedIterator<Item = Result<UserValue>> + 'static>

Returns an iterator that scans through the entire tree, returning values only.

fn flush_memtable( &self, segment_id: SegmentId, memtable: &Arc<Memtable>, seqno_threshold: SeqNo, ) -> Result<Option<Segment>>

Synchronously flushes a memtable to a disk segment.

fn register_segments(&self, segments: &[Segment]) -> Result<()>

Atomically registers flushed disk segments into the tree, removing their associated sealed memtables.

fn lock_active_memtable(&self) -> RwLockWriteGuard<'_, Arc<Memtable>>

Write-locks the active memtable for exclusive access

fn clear_active_memtable(&self)

Clears the active memtable atomically.

fn set_active_memtable(&self, memtable: Memtable)

Sets the active memtable.

fn add_sealed_memtable(&self, id: u64, memtable: Arc<Memtable>)

Adds a sealed memtables.

fn compact( &self, strategy: Arc<dyn CompactionStrategy>, seqno_threshold: SeqNo, ) -> Result<()>

Performs compaction on the tree’s levels, blocking the caller until it’s done.

fn get_next_segment_id(&self) -> SegmentId

Returns the next segment’s ID.

fn tree_config(&self) -> &Config

Returns the tree config.

fn active_memtable_size(&self) -> u32

Returns the approximate size of the active memtable in bytes.

fn tree_type(&self) -> TreeType

Returns the tree type.

fn rotate_memtable(&self) -> Option<(u64, Arc<Memtable>)>

Seals the active memtable, and returns a reference to it.

fn segment_count(&self) -> usize

Returns the amount of disk segments currently in the tree.

fn level_segment_count(&self, idx: usize) -> Option<usize>

Returns the amount of segments in levels[idx].

fn approximate_len(&self) -> usize

Approximates the amount of items in the tree.

fn disk_space(&self) -> u64

Returns the disk space usage.

fn get_highest_memtable_seqno(&self) -> Option<SeqNo>

Returns the highest sequence number of the active memtable.

fn get_highest_persisted_seqno(&self) -> Option<SeqNo>

Returns the highest sequence number that is flushed to disk.

fn snapshot(&self, seqno: SeqNo) -> Snapshot

Opens a read-only point-in-time snapshot of the tree

fn get<K: AsRef<[u8]>>( &self, key: K, seqno: Option<SeqNo>, ) -> Result<Option<UserValue>>

Retrieves an item from the tree.

fn range<K: AsRef<[u8]>, R: RangeBounds<K>>( &self, range: R, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Box<dyn DoubleEndedIterator<Item = Result<KvPair>> + 'static>

Returns an iterator over a range of items.

fn prefix<K: AsRef<[u8]>>( &self, prefix: K, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Box<dyn DoubleEndedIterator<Item = Result<KvPair>> + 'static>

Returns an iterator over a prefixed set of items.

fn insert<K: Into<UserKey>, V: Into<UserValue>>( &self, key: K, value: V, seqno: SeqNo, ) -> (u32, u32)

Inserts a key-value pair into the tree.

fn remove<K: Into<UserKey>>(&self, key: K, seqno: SeqNo) -> (u32, u32)

Removes an item from the tree.

fn remove_weak<K: Into<UserKey>>(&self, key: K, seqno: SeqNo) -> (u32, u32)

Removes an item from the tree.

fn major_compact(&self, target_size: u64, seqno_threshold: SeqNo) -> Result<()>

Performs major compaction, blocking the caller until it’s done.

fn get_highest_seqno(&self) -> Option<SeqNo>

Returns the highest sequence number.

fn blob_file_count(&self) -> usize

Returns the amount of blob files currently in the tree.

fn len( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Result<usize>

Scans the entire tree, returning the amount of items.

fn is_empty( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Result<bool>

Returns true if the tree is empty.

fn first_key_value( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Result<Option<KvPair>>

Returns the first key-value pair in the tree. The key in this pair is the minimum key in the tree.

fn last_key_value( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Result<Option<KvPair>>

Returns the last key-value pair in the tree. The key in this pair is the maximum key in the tree.

fn iter( &self, seqno: Option<SeqNo>, index: Option<Arc<Memtable>>, ) -> Box<dyn DoubleEndedIterator<Item = Result<KvPair>> + 'static>

Returns an iterator that scans through the entire tree.

fn snapshot_at(&self, seqno: SeqNo) -> Snapshot

Opens a snapshot of this partition with a given sequence number

fn contains_key<K: AsRef<[u8]>>( &self, key: K, seqno: Option<SeqNo>, ) -> Result<bool>

Returns true if the tree contains the specified key.

impl Clone for Tree

fn clone(&self) -> Tree

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Deref for Tree

type Target = TreeInner

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl From<Tree> for AnyTree

fn from(v: Tree) -> AnyTree

Converts to this type from the input type.

impl TryInto<Tree> for AnyTree

type Error = &'static str

The type returned in the event of a conversion error.

fn try_into(self) -> Result<Tree, <Self as TryInto<Tree>>::Error>

Performs the conversion.