Designing Vertical Processors in Monolithic 3D
Designing Vertical Processors in Monolithic 3D
复制标题
在 Monolithic 3D 中设计垂直处理器
DOI：
10.1145/3307650.3322233
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
J. Torrellas
中科院分区：
文献类型：
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作者：
Bhargava Gopireddy;J. Torrellas
在堆叠层上垂直布置的处理器可以从减少的电线延迟，低能消耗和少量足迹中受益。可以通过Monolithic 3D（M3D）启用这种设计，该技术可提供短线长度，良好的热能性能和高积分。在当前的M3D技术中，由于制造限制，堆栈中的层是不对称的：最底部的层具有相对较高的性能。在本文中，我们研究了如何将M3D的处理器划分。考虑到顶层具有较低的晶体管，我们将逻辑和存储结构分为两层。在逻辑结构中，我们将关键路径放在底层中。在存储结构中，我们不平等地对硬件进行了分配，分配给具有较大访问晶体管的较少端口，或者较短的比特电池子阵列，带有较大的bitcell。我们发现，通过对M3D技术的保守假设，M3D核心平均执行应用程序比2D核心快25％，而能量却少了39％。有了积极的技术假设，M3D核心的表现甚至更好：它的平均比2D核心快38％，并且能量减少了41％。此外，在类似的功率预算下，M3D多机可以使用两倍的核心，是2D多核的两倍，平均执行申请速度快92％，能量减少39％。最后，M3D芯是热效率的。
A processor laid out vertically in stacked layers can benefit from reduced wire delays, low energy consumption, and a small footprint. Such a design can be enabled by Monolithic 3D (M3D), a technology that provides short wire lengths, good thermal properties, and high integration. In current M3D technology, due to manufacturing constraints, the layers in the stack are asymmetric: the bottom-most one has a relatively higher performance. In this paper, we examine how to partition a processor for M3D. We partition logic and storage structures into two layers, taking into account that the top layer has lower-performance transistors. In logic structures, we place the critical paths in the bottom layer. In storage structures, we partition the hardware unequally, assigning to the top layer fewer ports with larger access transistors, or a shorter bitcell subarray with larger bitcells. We find that, with conservative assumptions on M3D technology, an M3D core executes applications on average 25% faster than a 2D core, while consuming 39% less energy. With aggressive technology assumptions, the M3D core performs even better: it is on average 38% faster than a 2D core and consumes 41% less energy. Further, under a similar power budget, an M3D multicore can use twice as many cores as a 2D multicore, executing applications on average 92% faster with 39% less energy. Finally, an M3D core is thermally efficient.