本研究著重在探討如何建立一個成本最低的配置，也就是在特定的效能需求的應用情況下，怎麼樣的配置可以有最低的建置成本，以及最高的儲存容量。本研究以實務為出發點探討不同RAID模型以及不同類型之儲存媒體在存取效能、資料保護能力以及建置成本上的差異。並希望透過各種不同的測試及實驗，了解磁碟陣列使用不同的儲存體及各種RAID level在存取效能、資料保護能力及建置成本之變化及差異，加以歸納整理。以期能針對不同應用需求找到的最適合的配置組態。
由測試結果中可以發現幾個現象，首先是不同的陣列控制卡所測得的效能會有所差異，這樣的差異在應用環境的模擬測試結果更為明顯。此外，SSD在相同的條件下，雖然單一磁碟的循序存取效能高於磁盤式硬碟，但是組成陣列後的總體循序存取效能卻低於磁盤式硬碟。這樣的結果顯示SSD使用在SAS的陣列環境中可能有相容的問題或者磁碟陣列卡需要針對SSD這個產品特別進行調校。
This study focus on how to build storage with most optimized configuration. We try to find out the most suitable configuration with lowest cost and maximum capacity under a specific application with specific performance requirement. This paper discuss the differences between different RAID models and different storage media on access performance, data protection ability and the setup cost. Through various tests and experiments to understand these differences, analyze and summarize these results. We hope to find out the optimized configuration for different application requirement.
We found something in these test and experiment results. At first, the storage performance may vary with RAID adapters, and this performance difference is more noticeable in application simulation performance tests. Second, in the same configuration and environment, SSD have better sequential access performance in single drive configuration than hard disk drive, but SSD have lower sequential access performance in array configuration compare with hard disk drive. The SSD slower array performance could because compatibility issue between SSD and SAS RAID adapters, or these SAS RAID adapters need optimized to be able to fully support SSD.
