Recap

Main Ideas of ARIES

• WAL (Write-Ahead Logging) with STEAL/NO-FORCE
• Fuzzy Checkpoints (snapshot of dirty page IDs)
• Redo everything since the earliest dirty page
• Undo transactions that never committed
• Write Compensation Log Records (CLRs) when undoing to survive failures during restarts

ARIES Components

Buffer Manager

PinPage, UnpinPage, ReadPage, WritePage, DirtyPageTabl

Recovery Manager

Restart, RecoverEarliestLSN, CreateLogRecord, RollbackTxn

Log Manager

ReadNextLogRecord, AppendLogRecord, GetMasterRecord, SetMasterRecord

Transaction Manager

GetRecordInfo, SetRecordInfo, ActiveTxnTable

Disk Manager

ReadBlock, WriteBlock