Instant Recovery with Write-Ahead Logging: Page Repair, System Restart, Media Restore, and System Failover, Second Edition
暫譯: 即時恢復與預寫日誌:頁面修復、系統重啟、媒體還原與系統故障轉移(第二版)
Goetz Graefe, Wey Guy, Caetano Sauer
- 出版商: Morgan & Claypool
- 出版日期: 2016-04-29
- 售價: $1,780
- 貴賓價: 9.5 折 $1,691
- 語言: 英文
- 頁數: 132
- 裝訂: Paperback
- ISBN: 1627058729
- ISBN-13: 9781627058728
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商品描述
Traditional theory and practice of write-ahead logging and of database recovery focus on three failure classes: transaction failures (typically due to deadlocks) resolved by transaction rollback; system failures (typically power or software faults) resolved by restart with log analysis, "redo," and "undo" phases; and media failures (typically hardware faults) resolved by restore operations that combine multiple types of backups and log replay.
The recent addition of single-page failures and single-page recovery has opened new opportunities far beyond the original aim of immediate, lossless repair of single-page wear-out in novel or traditional storage hardware. In the contexts of system and media failures, efficient single-page recovery enables on-demand incremental "redo" and "undo" as part of system restart or media restore operations. This can give the illusion of practically instantaneous restart and restore: instant restart permits processing new queries and updates seconds after system reboot and instant restore permits resuming queries and updates on empty replacement media as if those were already fully recovered. In the context of node and network failures, instant restart and instant restore combine to enable practically instant failover from a failing database node to one holding merely an out-of-date backup and a log archive, yet without loss of data, updates, or transactional integrity.
In addition to these instant recovery techniques, the discussion introduces self-repairing indexes and much faster offline restore operations, which impose no slowdown in backup operations and hardly any slowdown in log archiving operations. The new restore techniques also render differential and incremental backups obsolete, complete backup commands on a database server practically instantly, and even permit taking full up-to-date backups without imposing any load on the database server.
Compared to the first version of this book, this second edition adds sections on applications of single-page repair, instant restart, single-pass restore, and instant restore. Moreover, it adds sections on instant failover among nodes in a cluster, applications of instant failover, recovery for file systems and data files, and the performance of instant restart and instant restore.
商品描述(中文翻譯)
傳統的寫前日誌(write-ahead logging)和資料庫恢復的理論與實踐專注於三種故障類別:交易故障(通常由死鎖引起)透過交易回滾解決;系統故障(通常是電力或軟體故障)透過重啟並進行日誌分析、重做('redo')和撤銷('undo')階段來解決;以及媒體故障(通常是硬體故障)透過結合多種備份和日誌重播的恢復操作來解決。
最近新增的單頁故障和單頁恢復開啟了超越原始目標的新機會,即在新型或傳統儲存硬體中即時、無損地修復單頁磨損。在系統和媒體故障的背景下,高效的單頁恢復使得在系統重啟或媒體恢復操作中能夠按需增量地進行重做和撤銷。這可以給人一種幾乎瞬時重啟和恢復的錯覺:即時重啟允許在系統重啟幾秒後處理新的查詢和更新,而即時恢復則允許在空的替換媒體上恢復查詢和更新,彷彿這些媒體已經完全恢復。在節點和網路故障的背景下,即時重啟和即時恢復結合起來,使得從故障的資料庫節點幾乎瞬時切換到僅持有過時備份和日誌檔案的節點,卻不會損失數據、更新或交易完整性。
除了這些即時恢復技術,討論還引入了自我修復索引和更快的離線恢復操作,這些操作不會對備份操作造成任何延遲,且對日誌歸檔操作幾乎沒有延遲。新的恢復技術還使得差異備份和增量備份變得過時,幾乎瞬時完成資料庫伺服器上的完整備份命令,甚至允許在不對資料庫伺服器施加任何負載的情況下進行最新的完整備份。
與本書的第一版相比,第二版新增了有關單頁修復、即時重啟、單次恢復和即時恢復的應用部分。此外,還新增了有關叢集內節點之間即時故障轉移、即時故障轉移的應用、檔案系統和數據檔案的恢復,以及即時重啟和即時恢復的性能部分。