Struct WalManager 

pub struct WalManager { /* private fields */ }

WAL Manager

Manages write-ahead log for durability.

Implementations

impl WalManager

pub fn open(path: impl AsRef<Path>) -> KernelResult<Self>

Open or create a WAL file

pub fn append(&self, record: &mut WalRecord) -> KernelResult<LogSequenceNumber>

Append a record to the WAL

Returns the LSN of the appended record.

pub fn flush(&self) -> KernelResult<()>

Flush buffered writes to disk

pub fn sync(&self) -> KernelResult<LogSequenceNumber>

Sync WAL to durable storage (fsync)

pub fn durable_lsn(&self) -> LogSequenceNumber

Get the current durable LSN

pub fn next_lsn(&self) -> LogSequenceNumber

Get the next LSN that will be allocated

pub fn log_begin( &self, txn_id: TransactionId, ) -> KernelResult<LogSequenceNumber>

Log a transaction begin

pub fn log_commit( &self, txn_id: TransactionId, ) -> KernelResult<LogSequenceNumber>

Log a transaction commit

pub fn log_abort( &self, txn_id: TransactionId, ) -> KernelResult<LogSequenceNumber>

Log a transaction abort

pub fn log_update( &self, txn_id: TransactionId, page_id: PageId, redo_data: Bytes, undo_data: Bytes, ) -> KernelResult<LogSequenceNumber>

Log an update operation

pub fn log_checkpoint_begin(&self) -> KernelResult<LogSequenceNumber>

Log a checkpoint begin

pub fn log_checkpoint_end( &self, active_txns: &[TransactionId], ) -> KernelResult<LogSequenceNumber>

Log a checkpoint end with active transactions

pub fn checkpoint_lsn(&self) -> Option<LogSequenceNumber>

Get last checkpoint LSN

pub fn read_from( &self, start_lsn: LogSequenceNumber, ) -> KernelResult<Vec<WalRecord>>

Read all records from a given LSN

pub fn path(&self) -> &Path

Get WAL file path

pub fn truncate_before(&self, _lsn: LogSequenceNumber) -> KernelResult<()>

Truncate WAL up to a given LSN (for space reclamation after checkpoint)