本研究為物件儲存裝置設計了一個新穎的模擬架構。虛擬化模擬是將物件儲存裝置模擬器整合進虛擬機器內的模擬架構，不只在模擬速度與模擬精確度之間提供了一個理想的平衡，也同時解決了傳統儲存系統模擬架構所存在的兩種主要限制。一種限制是儲存系統模擬器本身會佔用模擬平台上處理器一部份之資源，另一種限制則是平台與模擬器間多餘花費在網路溝通上的時間。這兩種限制都會降低系統模擬的精確度。此模擬架構中的儲存系統模擬器不只使獨立於虛擬機器內的處理器，處理器與模擬器之間也不需要使用網路溝通。在此研究中，物件儲存裝置被實現為虛擬機器QEMU內的一個SCSI裝置。此裝置使用了非同步資料處理的設計，可以提高處理能力。此虛擬機器具備執行完整作業系統的能力，可以進行更貼近真實情境的測試及更深入的系統分析。
效能測試以檔案系統作為物件儲存裝置的比較對象。檔案系統的下層採用以區塊為儲存單位的傳統儲存裝置。物件儲存裝置由於可以將儲存資料的一部份管理轉移到儲存裝置本身，因此可以減輕系統整體的負荷，進而大幅增加儲存系統的資料傳輸效能。在測試數據中，物件儲存裝置的資料傳輸能力在最佳情況下可以比傳統檔案系統多出約436% 的效能。而在資料庫負荷能力的測試中，物件儲存裝置的效能在最佳情況下可以超出傳統檔案系統約666%。研究結果顯示，使用物件儲存裝置的儲存架構是高資料傳輸需求下的理想選擇。

This work presents a new emulation framework for object-based storage devices (OSDs). The virtual storage emulation framework integrates an object-based storage emulator with a virtual machine. The OSD model in this work not only provides a respectable balance between the emulation speed and accuracy, but also avoids the common problems with conventional storage emulation frameworks. It resolves the limitations of host CPU resource consumption and network communication overhead found in other frameworks. The storage emulator in the virtual machine runs independently of the emulated CPU, and no network messages are required for communication. The OSD model is implemented as a SCSI target in QEMU. It implements asynchronous I/O request processing to improve its throughput. Operating systems can be run inside QEMU to provide a realistic workload and a more in-depth analysis of the system.
The OSD model is compared to a traditional file system on top of a block device. The offloading of storage management into the device dramatically increases the throughput of the storage system. The benchmark results demonstrate an I/O performance improvement of 436% in the best case. Synthetic database workload performance improves by 666% in the best case. The results suggest that the object-based storage architecture is an ideal choice for throughput machines, especially under heavy workloads.

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