在晶片的耗能上，最主要分為動態能耗與靜態能耗。然而隨著製程的進步，靜態能耗已經占整體功率中的50%。因此在靜態能耗上的設計已經越來越重要。在嵌入式系統中，草稿式記憶體相比於傳統的快取記憶體，擁有較少的耗電量以及總面積的減少。目前現有的研究已經提出在草稿式記憶體中分成許多區塊來進一步減少能量的消耗。現有的研究中，為了得知程式中的記憶體的存取模式，必須在程式執行前便分析程式的行為，再根據這些行為來分配記憶體。
在此篇論文中，我們提出了一個不需要事前分析的多分區草稿式記憶體線上分群方法之設計。此方法根據目前草稿式記憶體的頁訪問程度來區分熱度。熱的資料與冷的資料分配到不同的區塊。讓放置冷資料的區塊可以增加閒置時間並進入低電位模式來減少的靜態能耗。最後結果顯示，我們的方法和傳統的超時方法相比。在32KB 4-bank中，能量與延遲乘積平均可減少18.09%、32KB 8-bank中，可減少15.71%、16KB 4-bank中，可減少13.44%。16KB 8-bank中，可減少10.05%。除此之外，此方法所造成的額外的面積開銷會占據晶片記憶體總面積的0.72%。

Power consumption of on-chip memory is divided two parts, dynamic power and leakage power. With the scaling of CMOS devices, the portion of leakage power consumption increases and it can go over 50% of total power consumption in a CMOS device. Scratchpad memory (SPM), a software-controlled on-chip memory, has less access energy and higher area density when compared to an ordinary cache. Multi-bank SPM was proposed to further reduce the energy consumption.
This paper proposed OCBAS, a novel Online Data Clustering for Multi-bank Scratchpad memory. OCBAS identifies the hotness of each SPM page and clusters pages with different degrees of hotness into different SPM banks, increasing idleness for cold SPM banks and hence reducing the leakage energy of the SPM. Moreover, OCBAS allows cold SPM banks to enter the low power mode more aggressively, further reducing the leakage energy. Offline profiling is not required in OCBAS. The evaluation results show that OCBAS can reduce the energy delay product (EDP) by up to 37.71% (18.09% on average) in 32KB 4-bank, 25.33% (15.71% on average) in 32KB 8-bank, 28.99% (13.45% on average) in 16KB 4-bank, 30.18% (10.05% on average) in 16KB 8-bank SPM, compared to conventional time-out-based policy. Moreover, the area overhead of the hardware support is insignificant (about 0.72%).

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