臺灣博碩士論文加值系統

近年來，自旋轉移力矩隨機存取記憶體(spin transfer torque random access memory，STT-RAM) 的崛起吸引了學術界及產業界的注意。相較於DRAM，STTRAM 在結構上更加簡單，並且有較快的存取速度與較低的功率消耗。然而，STT-RAM 目前並無法完全取代DRAM，因為STT-RAM 目前仍在發展階段，因此 STT-RAM 的單位儲存成本仍比DRAM 高出許多。在本篇論文中，我們提出了一個STT-RAM/DRAM 混合型記憶體管理機制，結合DRAM 與少量STT-RAM，做為主機端的主記憶體。實驗結果顯示，2GB 的DRAM 結合128MB 的STT-RAM 可以減少記憶體單元58.07% 的功耗，並且提昇42.8% 的系統效能。

In recent years, the emerging of STT-RAM (Spin Transfer Torque Random Access
Memory) has drawn a lot attentions from both academia and industry. Compared with DRAM, STT-RAM has simpler structure, lower access latency, and lower power consumption. However, STT-RAM cannot replace DRAM since STT-RAM is still in the earlier stage of development and its cost is much higher than DRAM. In this paper, we present a STT-RAM/DRAM hybrid memory management scheme that combines a small amount of STT-RAM with DRAM as the main memory for the host. The experiment results showed that 2GB DRAM with 128MB STT-RAM can reduce 58.07% power consumption of memory unit and improve 42.8% system performance.

1 Introduction
2 Background
2.1 DRAM
2.2 STT-RAM
2.3 Mapping work principle
2.4 Hybrid memory
2.5 Hybrid DRAM & STT-RAM 記憶體架構
3 研究方法
3.1 HDMT
3.2 實體記憶體位置編排
3.3 Front Mapping Area
3.4 Replacement Table
3.5 STT-RAM region item victim policy
3.6 CPU 讀操作需求流程圖
3.7 CPU 寫操作需求流程圖
4 實驗設計
4.1 模擬系統參數
4.2 Trace 設計與產生方式
5 實驗結果與分析
5.1 Hit ratio
5.2 省電效能比較與分析
5.3 系統記憶體讀寫操作比例分析
5.4 系統效能分析
6 結論

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