An energy-efficient near-data processing accelerator for DNNs to optimize memory accesses

The constant growth of DNNs makes them challenging to implement and run efficiently on traditional computecentric architectures. Some accelerators have attempted to add more compute units and on-chip buffers to solve the memory wall problem without much success, and sometimes even worsening the issu...

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Detalles Bibliográficos
Autores: Khabbazan, Bahareh|||0000-0001-6726-2804, Sabri Abrebekoh, Mohammad|||0000-0002-3113-5392, Riera Villanueva, Marc|||0000-0002-2768-5703, González Colás, Antonio María|||0000-0002-0009-0996
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/423070
Acceso en línea:https://hdl.handle.net/2117/423070
https://dx.doi.org/10.1016/j.sysarc.2024.103320
Access Level:acceso abierto
Palabra clave:DNN
NDP
Accelerators
Quantization
Exponential
Transformer
Àrees temàtiques de la UPC::Informàtica::Arquitectura de computadors
Descripción
Sumario:The constant growth of DNNs makes them challenging to implement and run efficiently on traditional computecentric architectures. Some accelerators have attempted to add more compute units and on-chip buffers to solve the memory wall problem without much success, and sometimes even worsening the issue since more compute units also require higher memory bandwidth. Prior works have proposed the design of memorycentric architectures based on the Near-Data Processing (NDP) paradigm. NDP seeks to break the memory wall by moving the computations closer to the memory hierarchy, reducing the data movements and their cost as much as possible. The 3D-stacked memory is especially appealing for DNN accelerators due to its high-density/low-energy storage and near-memory computation capabilities to perform the DNN operations massively in parallel. However, memory accesses remain as the main bottleneck for running modern DNNs efficiently. To improve the efficiency of DNN inference we present QeiHaN, a hardware accelerator that implements a 3D-stacked memory-centric weight storage scheme to take advantage of a logarithmic quantization of activations. In particular, since activations of FC and CONV layers of modern DNNs are commonly represented as powers of two with negative exponents, QeiHaN performs an implicit in-memory bit-shifting of the DNN weights to reduce memory activity. Only the meaningful bits of the weights required for the bit-shift operation are accessed. Overall, QeiHaN reduces memory accesses by 25% compared to a standard memory organization. We evaluate QeiHaN on a popular set of DNNs. On average, QeiHaN provides4.3¿speedup and3.5¿energy savings over a Neurocube-like accelerator.