Struct lsm_tree::SequenceNumberCounter

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

Thread-safe sequence number generator

Examples

let tree = Config::new(path).open()?;

let seqno = SequenceNumberCounter::default();

// Do some inserts...
tree.insert("a".as_bytes(), "abc", seqno.next());
tree.insert("b".as_bytes(), "abc", seqno.next());
tree.insert("c".as_bytes(), "abc", seqno.next());

// Maybe create a snapshot
let snapshot = tree.snapshot(seqno.get());

// Create a batch
let batch_seqno = seqno.next();
tree.remove("a".as_bytes(), batch_seqno);
tree.remove("b".as_bytes(), batch_seqno);
tree.remove("c".as_bytes(), batch_seqno);

Implementations

impl SequenceNumberCounter

pub fn new(prev: SeqNo) -> Self

Creates a new counter, setting it to some previous value

pub fn get(&self) -> SeqNo

Gets the next sequence number, without incrementing the counter.

This should only be used when creating a snapshot.

pub fn next(&self) -> SeqNo

Gets the next sequence number.

Trait Implementations

impl Clone for SequenceNumberCounter

fn clone(&self) -> SequenceNumberCounter

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for SequenceNumberCounter

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

Formats the value using the given formatter.

impl Default for SequenceNumberCounter

fn default() -> SequenceNumberCounter

Returns the “default value” for a type.

impl Deref for SequenceNumberCounter

type Target = Arc<AtomicU64>

The resulting type after dereferencing.

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

Dereferences the value.