Disk arrays, or RAIDs, have become the trend to increase the capacity and bandwidth of most storage system. Software RAID is the easy and economical way to activate a RAID system. RAID-5 is a common implementation taken by enterprise or business companies. However, the RAID-5 has small write issue, especially in the environments where small requests dominate the workload. There are many theses proposed their solutions to solve this point. In this paper, we also try to propose another method to enhance the performance of disk I/O on RAID-5. We use a part of memory as our cache to storage the frequent data on RAID-5, and we can reduce the frequency of access disk. The simulation results show that our design can improve the performance about 7%~12% regarding progress which need to frequently small write.

磁碟陣列或稱RAID，增加儲存系統的容量和頻寬，已經成為發展的趨勢。軟件RAID是一種簡單而且經濟的辦法去啟動一個RAID的系統。RAID-5 是一種企業或商業公司常見的實作方式。然而尤其在小量寫支配工作量的環境□，RAID-5有小量寫的問題。有很多論文對於這點提出他們的解決之道。在本篇論文中，我們也試著去提出另一種方法去加強RAID-5上面硬碟輸入輸出的性能。我們使用記憶體當作我們的快速儲存區去儲存RAID-5上面經常出現的資料，這樣一來我們可以減少它存取硬碟的量。實驗的結果顯示對於那些經常需要去小量寫的程式，我們的設計可以增進大約7%~12%的效能。

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