Struct VersionStore 

pub struct VersionStore { /* private fields */ }

Lock-free version store using DashMap

Provides O(1) key lookup + O(log V) version lookup per key.

Implementations

impl VersionStore

pub fn new() -> Self

Create new version store

pub fn insert_uncommitted( &self, key: &[u8], value: Option<Vec<u8>>, txn_id: u64, epoch: u32, ) -> Result<()>

Insert a new uncommitted version

pub fn commit(&self, key: &[u8], txn_id: u64, commit_ts: u64) -> bool

Commit a version

pub fn abort(&self, key: &[u8], txn_id: u64)

Abort uncommitted version

pub fn get( &self, key: &[u8], snapshot_ts: u64, current_txn_id: Option<u64>, ) -> Option<Vec<u8>>

Read value at snapshot timestamp

pub fn contains(&self, key: &[u8], snapshot_ts: u64) -> bool

Check if key exists at snapshot

pub fn gc(&self, min_epoch: u32, min_snapshot_ts: u64) -> usize

Run garbage collection

Removes old versions that are no longer visible to any reader.

pub fn len(&self) -> usize

Get number of keys

pub fn is_empty(&self) -> bool

Check if empty

pub fn stats(&self) -> &VersionStoreStats

Get statistics

Trait Implementations

impl Default for VersionStore

fn default() -> Self

Returns the “default value” for a type.

impl MvccStore for VersionStore

fn mvcc_get( &self, key: &[u8], snapshot_ts: u64, txn_id: Option<u64>, ) -> Option<Vec<u8>>

Read the visible value at snapshot_ts, optionally seeing own writes from txn_id.

fn mvcc_put( &self, key: &[u8], value: Option<Vec<u8>>, txn_id: u64, ) -> Result<(), MvccStoreError>

Write a value (or tombstone None) as uncommitted for the given transaction.

fn mvcc_commit_key(&self, key: &[u8], txn_id: u64, commit_ts: u64) -> bool

Commit one key’s uncommitted write. Returns true if found and committed.

fn mvcc_abort_key(&self, key: &[u8], txn_id: u64)

Abort one key’s uncommitted write.

fn mvcc_has_conflict(&self, key: &[u8], txn_id: u64) -> bool

Check if there’s an uncommitted write conflict on a key.

fn mvcc_gc(&self, min_ts: u64) -> MvccGcStats

Run garbage collection. Returns statistics.

fn mvcc_key_count(&self) -> usize

Number of distinct keys in the store.