節能議題已經成為目前儲存技術上最受重視的問題，根據報告指出儲存系統所消耗的電力大約佔了整個資料中心的50%，又另一個數據指出以電費來估計的話，儲存系統所消耗的電費為整個資料中心的27%。

我們分析了兩個真正運作的系統的使用者行為並從中得到了一些啟發。根據我們的分析，在某些特定的系統上(例：網頁伺服器以及數位文獻保存系統)，有很大的機會可以藉著關掉閒置的硬碟來達到節能的目的。因此，我們提出了CacheRAID，一個節能的RAID 架構儲存系統。我們設計了三個可自動調整的寫入策略來使CacheRAID節省能源。首先，我們利用檔案被寫入的時間來將檔案進行特殊的配
置以集中彼此有相關性的檔案在某些硬碟中。第二，動態的調整檔案寫入硬碟的時間，以得到更多連續寫入的機會並藉此避免速度較慢的隨機寫入的次數。最後，硬碟監控的機制負責管理硬碟的狀態以及關閉閒置的硬碟。我們實作了CacheRAID 並且實際的運作並測量耗電量，而實驗結果顯示了在特定的系統使用狀況中，CacheRAID最多可以節省71%的能源

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