Struct MvccTransactionManager 

pub struct MvccTransactionManager { /* private fields */ }

Full MVCC Transaction Manager with WAL and Group Commit

Provides ACID transactions with:

• Multi-Version Concurrency Control
• WAL-based durability
• Group commit for high throughput
• SSI for serializability (optional)

Uses DashMap for version chains to reduce lock contention:

• Striped locking: O(1) contention with ~64 internal shards
• Lock-free reads via read() method for most cases
• Fine-grained per-key locking for writes

Implementations

impl MvccTransactionManager

pub fn new<P: AsRef<Path>, F>(wal_path: P, apply_fn: F) -> Result<Self>

where F: Fn(&[u8], &[u8]) -> Result<()> + Send + Sync + 'static,

Create a new MVCC transaction manager

pub fn begin(&self, isolation_level: IsolationLevel) -> Result<u64>

Begin a new transaction with specified isolation level

pub fn begin_default(&self) -> Result<u64>

Begin with default snapshot isolation

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

Read a key within a transaction

pub fn write(&self, txn_id: u64, key: Vec<u8>, value: Vec<u8>) -> Result<()>

Write a key within a transaction

pub fn commit(&self, txn_id: u64) -> Result<u64>

Commit a transaction

pub fn abort(&self, txn_id: u64) -> Result<()>

Abort a transaction

pub fn delete(&self, txn_id: u64, key: &[u8]) -> Result<bool>

Delete a key within a transaction

pub fn gc(&self) -> usize

Garbage collect old versions

pub fn recover(&self) -> Result<RecoveryStats>

Recover from WAL after crash

pub fn current_timestamp(&self) -> u64

Get current timestamp

pub fn active_count(&self) -> usize

Get active transaction count