Vau Da Muntanialas: Energy-Efficient Multi-Die Scalable Acceleration of RNN Inference


METADATA ONLY
Loading...

Date

2022-01

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric
METADATA ONLY

Data

Rights / License

Abstract

Recurrent neural networks such as Long Short-Term Memories (LSTMs) learn temporal dependencies by keeping an internal state, making them ideal for time-series problems such as speech recognition. However, the output-to-input feedback creates distinctive memory bandwidth and scalability challenges in designing accelerators for RNNs. We present Muntaniala, an RNN accelerator architecture for LSTM inference with a silicon-measured energy-efficiency of 3.25 TOP/s/W and performance of 30.53 GOP/s in UMC 65nm technology. The scalable design of Muntaniala allows running large RNN models by combining multiple tiles in a systolic array. We keep all parameters stationary on every die in the array, drastically reducing the I/O communication to only loading new features and sharing partial results with other dies. For quantifying the overall system power, including I/O power, we built Vau da Muntanialas, to the best of our knowledge, the first demonstration of a systolic multi-chip-on-PCB array of RNN accelerator. Our multi-die prototype performs LSTM inference with 192 hidden states in 330 μs with a total system power of 9.0 mW at 10 MHz consuming 2.95 μJ. Targeting the 8/16-bit quantization implemented in Muntaniala, we show a phoneme error rate (PER) drop of approximately 3% with respect to floating-point (FP) on a 3L-384NH-123NI LSTM network on the TIMIT dataset.

Publication status

published

Editor

Book title

Volume

69 (1)

Pages / Article No.

244 - 257

Publisher

IEEE

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

LSTM; neural network; recurrent neural network; deep learning; hardware; systolic; multi-chip; accelerator

Organisational unit

03996 - Benini, Luca / Benini, Luca check_circle

Notes

Funding

180625 - Heterogeneous Computing Systems with Customized Accelerators (SNF)

Related publications and datasets