Module wal 

Write-Ahead Log — append-only log for crash recovery.

WAL entry format on disk:

[length: u32][lsn: u64][type: u8][page_id: u64][compressed_data: ...][crc32: u32]

• length — byte count of the payload (lsn + type + page_id + compressed_data).
• compressed_data — the data portion compressed with LZ4.
• crc32 — checksum over the entire payload.

Structs

Wal

Append-only write-ahead log.

WalEntry

A single WAL entry (in-memory representation).

Enums

WalEntryType

WAL entry type discriminant.

Type Aliases

Lsn

Log Sequence Number.