PipeOrgan: Efficient Inter-operation Pipelining with Flexible Spatial Organization and Interconnects

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Garg, Raveesh, Kwon, Hyoukjun, Qin, Eric, Chen, Yu-Hsin, Krishna, Tushar, Lai, Liangzhen
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866917656259461120
author Garg, Raveesh
Kwon, Hyoukjun
Qin, Eric
Chen, Yu-Hsin
Krishna, Tushar
Lai, Liangzhen
author_facet Garg, Raveesh
Kwon, Hyoukjun
Qin, Eric
Chen, Yu-Hsin
Krishna, Tushar
Lai, Liangzhen
contents Because of the recent trends in Deep Neural Networks (DNN) models being memory-bound, inter-operator pipelining for DNN accelerators is emerging as a promising optimization. Inter-operator pipelining reduces costly on-chip global memory and off-chip memory accesses by forwarding the output of a layer as the input of the next layer within the compute array, which is proven to be an effective optimization by previous works. However, the design space of inter-operator pipelining is huge, and the space is not yet fully explored. In particular, identifying the right depth and granularity of pipelining (or no pipelining at all) is significantly dependent on the layer shapes and data volumes of weights and activations, and these are different even within a domain. Moreover, works divide the substrate into large chunks and map one layer onto each chunk, which requires communicating halfway through or through the global buffer. However, for fine-grained inter-operation pipelining, placing the corresponding consumer of the next layer tile close to the producer tile of the current layer is a better way to exploit fine-grained spatial reuse. In order to support variable number of layers (ie the right depth) and support multiple spatial organizations of layers (in accordance with the pipelining granularity) on the substrate, we propose PipeOrgan, a new class of spatial data organization strategy for energy efficient and congestion-free communication between the PEs for various pipeline depth and granularity. PipeOrgan takes advantage of flexible spatial organization and can allocate layers to PEs based on the granularity of pipelining. We also propose changes to the conventional mesh topology to improve the performance of coarse-grained allocation. PipeOrgan achieves 1.95x performance improvement over the state-of-the-art pipelined dataflow on XR-bench workloads.
format Preprint
id arxiv_https___arxiv_org_abs_2405_01736
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle PipeOrgan: Efficient Inter-operation Pipelining with Flexible Spatial Organization and Interconnects
Garg, Raveesh
Kwon, Hyoukjun
Qin, Eric
Chen, Yu-Hsin
Krishna, Tushar
Lai, Liangzhen
Hardware Architecture
Because of the recent trends in Deep Neural Networks (DNN) models being memory-bound, inter-operator pipelining for DNN accelerators is emerging as a promising optimization. Inter-operator pipelining reduces costly on-chip global memory and off-chip memory accesses by forwarding the output of a layer as the input of the next layer within the compute array, which is proven to be an effective optimization by previous works. However, the design space of inter-operator pipelining is huge, and the space is not yet fully explored. In particular, identifying the right depth and granularity of pipelining (or no pipelining at all) is significantly dependent on the layer shapes and data volumes of weights and activations, and these are different even within a domain. Moreover, works divide the substrate into large chunks and map one layer onto each chunk, which requires communicating halfway through or through the global buffer. However, for fine-grained inter-operation pipelining, placing the corresponding consumer of the next layer tile close to the producer tile of the current layer is a better way to exploit fine-grained spatial reuse. In order to support variable number of layers (ie the right depth) and support multiple spatial organizations of layers (in accordance with the pipelining granularity) on the substrate, we propose PipeOrgan, a new class of spatial data organization strategy for energy efficient and congestion-free communication between the PEs for various pipeline depth and granularity. PipeOrgan takes advantage of flexible spatial organization and can allocate layers to PEs based on the granularity of pipelining. We also propose changes to the conventional mesh topology to improve the performance of coarse-grained allocation. PipeOrgan achieves 1.95x performance improvement over the state-of-the-art pipelined dataflow on XR-bench workloads.
title PipeOrgan: Efficient Inter-operation Pipelining with Flexible Spatial Organization and Interconnects
topic Hardware Architecture
url https://arxiv.org/abs/2405.01736